402640992 has 288 divisors, whose sum is σ = 1313728416. Its totient is φ = 116121600.

The previous prime is 402640981. The next prime is 402640999. The reversal of 402640992 is 299046204.

402640992 is a `hidden beast` number, since 4 + 0 + 2 + 640 + 9 + 9 + 2 = 666.

It is a tau number, because it is divible by the number of its divisors (288).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (402640999) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 6600642 + ... + 6600702.

It is an arithmetic number, because the mean of its divisors is an integer number (4561557).

Almost surely, 2^402640992 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 402640992, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (656864208).

402640992 is an abundant number, since it is smaller than the sum of its proper divisors (911087424).

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

402640992 is a wasteful number, since it uses less digits than its factorization.

402640992 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 174 (or 163 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 36.

The square root of 402640992 is about 20065.9161764421. The cubic root of 402640992 is about 738.4243268909.

The spelling of 402640992 in words is "four hundred two million, six hundred forty thousand, nine hundred ninety-two".