20139769856 has 32 divisors (see below), whose sum is σ = 40278990630. Its totient is φ = 10069868544.

The previous prime is 20139769817. The next prime is 20139769889. The reversal of 20139769856 is 65896793102.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 16285843456 + 3853926400 = 127616^2 + 62080^2 .

It is a tau number, because it is divible by the number of its divisors (32).

It is a super-2 number, since 2×20139769856² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 274541 + ... + 340076.

Almost surely, 2^20139769856 is an apocalyptic number.

It is an amenable number.

20139769856 is a deficient number, since it is larger than the sum of its proper divisors (20139220774).

20139769856 is an frugal number, since it uses more digits than its factorization.

20139769856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 614647 (or 614619 counting only the distinct ones).

The product of its (nonzero) digits is 4898880, while the sum is 56.

The spelling of 20139769856 in words is "twenty billion, one hundred thirty-nine million, seven hundred sixty-nine thousand, eight hundred fifty-six".