20667956 has 12 divisors (see below), whose sum is σ = 36255492. Its totient is φ = 10309248.

The previous prime is 20667943. The next prime is 20667967. The reversal of 20667956 is 65976602.

It can be written as a sum of positive squares in 2 ways, for example, as 9672100 + 10995856 = 3110^2 + 3316^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4235 + ... + 7698.

It is an arithmetic number, because the mean of its divisors is an integer number (3021291).

Almost surely, 2^20667956 is an apocalyptic number.

It is an amenable number.

20667956 is a deficient number, since it is larger than the sum of its proper divisors (15587536).

20667956 is a wasteful number, since it uses less digits than its factorization.

20667956 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12370 (or 12368 counting only the distinct ones).

The product of its (nonzero) digits is 136080, while the sum is 41.

The square root of 20667956 is about 4546.2023712105. The cubic root of 20667956 is about 274.4305837614.

The spelling of 20667956 in words is "twenty million, six hundred sixty-seven thousand, nine hundred fifty-six".