402969840 has 160 divisors (see below), whose sum is σ = 1537568256. Its totient is φ = 85017600.

The previous prime is 402969817. The next prime is 402969871. The reversal of 402969840 is 48969204.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a junction number, because it is equal to n+sod(n) for n = 402969792 and 402969801.

It is a congruent number.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 12615 + ... + 31065.

Almost surely, 2^402969840 is an apocalyptic number.

402969840 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 402969840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (768784128).

402969840 is an abundant number, since it is smaller than the sum of its proper divisors (1134598416).

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

402969840 is a wasteful number, since it uses less digits than its factorization.

402969840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18487 (or 18481 counting only the distinct ones).

The product of its (nonzero) digits is 124416, while the sum is 42.

The square root of 402969840 is about 20074.1086975238. The cubic root of 402969840 is about 738.6253026894.

The spelling of 402969840 in words is "four hundred two million, nine hundred sixty-nine thousand, eight hundred forty".