402839920 has 80 divisors (see below), whose sum is σ = 1072931328. Its totient is φ = 137790720.

The previous prime is 402839897. The next prime is 402839923. The reversal of 402839920 is 29938204.

402839920 is a nontrivial binomial coefficient, being equal to C(28385, 2).

It is a tau number, because it is divible by the number of its divisors (80).

It is a super-2 number, since 2×402839920² = 324560002291212800, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 402839920.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (402839923) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 453717 + ... + 454603.

Almost surely, 2^402839920 is an apocalyptic number.

402839920 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

402839920 is the 28384-th triangular number.

402839920 is the 9462-nd centered nonagonal number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 402839920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (536465664).

402839920 is an abundant number, since it is smaller than the sum of its proper divisors (670091408).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

402839920 is a wasteful number, since it uses less digits than its factorization.

402839920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1718 (or 1712 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 37.

The square root of 402839920 is about 20070.8724274756. The cubic root of 402839920 is about 738.5459150160.

The spelling of 402839920 in words is "four hundred two million, eight hundred thirty-nine thousand, nine hundred twenty".