65631690 has 48 divisors (see below), whose sum is σ = 173062656. Its totient is φ = 17253600.

The previous prime is 65631689. The next prime is 65631701. The reversal of 65631690 is 9613656.

65631690 is a `hidden beast` number, since 6 + 563 + 1 + 6 + 90 = 666.

It is a super-2 number, since 2×65631690² = 8615037464512200, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1255 + ... + 11525.

It is an arithmetic number, because the mean of its divisors is an integer number (3605472).

Almost surely, 2^65631690 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 65631690, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (86531328).

65631690 is an abundant number, since it is smaller than the sum of its proper divisors (107430966).

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

65631690 is a wasteful number, since it uses less digits than its factorization.

65631690 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10355 (or 10352 counting only the distinct ones).

The product of its (nonzero) digits is 29160, while the sum is 36.

The square root of 65631690 is about 8101.3387782514. The cubic root of 65631690 is about 403.3708675009.

The spelling of 65631690 in words is "sixty-five million, six hundred thirty-one thousand, six hundred ninety".