20687651252 has 6 divisors (see below), whose sum is σ = 36203389698. Its totient is φ = 10343825624.

The previous prime is 20687651251. The next prime is 20687651261. The reversal of 20687651252 is 25215678602.

It can be written as a sum of positive squares in only one way, i.e., 16567808656 + 4119842596 = 128716^2 + 64186^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20687651251) by changing a digit.

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 as a sum of consecutive naturals, namely, 2585956403 + ... + 2585956410.

It is an arithmetic number, because the mean of its divisors is an integer number (6033898283).

Almost surely, 2^20687651252 is an apocalyptic number.

It is an amenable number.

20687651252 is a deficient number, since it is larger than the sum of its proper divisors (15515738446).

20687651252 is a wasteful number, since it uses less digits than its factorization.

20687651252 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5171912817 (or 5171912815 counting only the distinct ones).

The product of its (nonzero) digits is 403200, while the sum is 44.

The spelling of 20687651252 in words is "twenty billion, six hundred eighty-seven million, six hundred fifty-one thousand, two hundred fifty-two".