331487640 has 320 divisors, whose sum is σ = 1241982720. Its totient is φ = 78624000.

The previous prime is 331487621. The next prime is 331487683. The reversal of 331487640 is 46784133.

331487640 is a `hidden beast` number, since 3 + 3 + 1 + 4 + 8 + 7 + 640 = 666.

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

It is a junction number, because it is equal to n+sod(n) for n = 331487595 and 331487604.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 2530375 + ... + 2530505.

It is an arithmetic number, because the mean of its divisors is an integer number (3881196).

Almost surely, 2^331487640 is an apocalyptic number.

331487640 is a gapful number since it is divisible by the number (30) 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 331487640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (620991360).

331487640 is an abundant number, since it is smaller than the sum of its proper divisors (910495080).

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

331487640 is a wasteful number, since it uses less digits than its factorization.

331487640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 236 (or 223 counting only the distinct ones).

The product of its (nonzero) digits is 48384, while the sum is 36.

The square root of 331487640 is about 18206.8020256167. The cubic root of 331487640 is about 692.0791727828.

The spelling of 331487640 in words is "three hundred thirty-one million, four hundred eighty-seven thousand, six hundred forty".