20767864 has 32 divisors (see below), whose sum is σ = 42124320. Its totient is φ = 9542016.

The previous prime is 20767847. The next prime is 20767871. The reversal of 20767864 is 46876702.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 41037 + ... + 41539.

It is an arithmetic number, because the mean of its divisors is an integer number (1316385).

Almost surely, 2^20767864 is an apocalyptic number.

It is an amenable number.

20767864 is an abundant number, since it is smaller than the sum of its proper divisors (21356456).

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

20767864 is a wasteful number, since it uses less digits than its factorization.

20767864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 919 (or 915 counting only the distinct ones).

The product of its (nonzero) digits is 112896, while the sum is 40.

The square root of 20767864 is about 4557.1771964671. The cubic root of 20767864 is about 274.8720683183.

The spelling of 20767864 in words is "twenty million, seven hundred sixty-seven thousand, eight hundred sixty-four".