20769864 has 32 divisors (see below), whose sum is σ = 53032320. Its totient is φ = 6775616.

The previous prime is 20769863. The next prime is 20769871. The reversal of 20769864 is 46896702.

It is not an unprimeable number, because it can be changed into a prime (20769863) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8079 + ... + 10334.

It is an arithmetic number, because the mean of its divisors is an integer number (1657260).

Almost surely, 2^20769864 is an apocalyptic number.

20769864 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

20769864 is an abundant number, since it is smaller than the sum of its proper divisors (32262456).

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

20769864 is a wasteful number, since it uses less digits than its factorization.

20769864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18469 (or 18465 counting only the distinct ones).

The product of its (nonzero) digits is 145152, while the sum is 42.

The square root of 20769864 is about 4557.3966252675. The cubic root of 20769864 is about 274.8808916698.

The spelling of 20769864 in words is "twenty million, seven hundred sixty-nine thousand, eight hundred sixty-four".