20513251312 has 20 divisors (see below), whose sum is σ = 39746842200. Its totient is φ = 10256001728.

The previous prime is 20513251309. The next prime is 20513251313. The reversal of 20513251312 is 21315231502.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20513251313) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 349563 + ... + 404005.

It is an arithmetic number, because the mean of its divisors is an integer number (1987342110).

Almost surely, 2^20513251312 is an apocalyptic number.

It is an amenable number.

20513251312 is a deficient number, since it is larger than the sum of its proper divisors (19233590888).

20513251312 is a wasteful number, since it uses less digits than its factorization.

20513251312 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 78000 (or 77994 counting only the distinct ones).

The product of its (nonzero) digits is 1800, while the sum is 25.

Adding to 20513251312 its reverse (21315231502), we get a palindrome (41828482814).

The spelling of 20513251312 in words is "twenty billion, five hundred thirteen million, two hundred fifty-one thousand, three hundred twelve".