16505631 has 12 divisors (see below), whose sum is σ = 24292008. Its totient is φ = 10795824.

The previous prime is 16505627. The next prime is 16505639. The reversal of 16505631 is 13650561.

It is a happy number.

16505631 is a `hidden beast` number, since 1 + 650 + 5 + 6 + 3 + 1 = 666.

It is not a de Polignac number, because 16505631 - 2² = 16505627 is a prime.

It is a super-2 number, since 2×16505631² = 544871709416322, which contains 22 as substring.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 16505595 and 16505604.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16505639) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 16825 + ... + 17778.

It is an arithmetic number, because the mean of its divisors is an integer number (2024334).

Almost surely, 2^16505631 is an apocalyptic number.

16505631 is a deficient number, since it is larger than the sum of its proper divisors (7786377).

16505631 is a wasteful number, since it uses less digits than its factorization.

16505631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34662 (or 34659 counting only the distinct ones).

The product of its (nonzero) digits is 2700, while the sum is 27.

The square root of 16505631 is about 4062.7122713773. The cubic root of 16505631 is about 254.6111258394.

The spelling of 16505631 in words is "sixteen million, five hundred five thousand, six hundred thirty-one".