402524640 has 672 divisors, whose sum is σ = 1784825280. Its totient is φ = 83607552.

The previous prime is 402524627. The next prime is 402524641. The reversal of 402524640 is 46425204.

It is a tau number, because it is divible by the number of its divisors (672).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (402524641) by changing a digit.

It is a polite number, since it can be written in 111 ways as a sum of consecutive naturals, for example, 13880146 + ... + 13880174.

It is an arithmetic number, because the mean of its divisors is an integer number (2655990).

Almost surely, 2^402524640 is an apocalyptic number.

402524640 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 402524640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (892412640).

402524640 is an abundant number, since it is smaller than the sum of its proper divisors (1382300640).

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

402524640 is a wasteful number, since it uses less digits than its factorization.

402524640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 86 (or 63 counting only the distinct ones).

The product of its (nonzero) digits is 7680, while the sum is 27.

The square root of 402524640 is about 20063.0167223177. The cubic root of 402524640 is about 738.3531920370.

Adding to 402524640 its reverse (46425204), we get a palindrome (448949844).

The spelling of 402524640 in words is "four hundred two million, five hundred twenty-four thousand, six hundred forty".