21250640252 has 12 divisors (see below), whose sum is σ = 37481445120. Its totient is φ = 10541655936.

The previous prime is 21250640251. The next prime is 21250640287. The reversal of 21250640252 is 25204605212.

It is a super-2 number, since 2×21250640252² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21250640251) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20915477 + ... + 20916492.

It is an arithmetic number, because the mean of its divisors is an integer number (3123453760).

Almost surely, 2^21250640252 is an apocalyptic number.

It is an amenable number.

21250640252 is a deficient number, since it is larger than the sum of its proper divisors (16230804868).

21250640252 is a wasteful number, since it uses less digits than its factorization.

21250640252 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41832100 (or 41832098 counting only the distinct ones).

The product of its (nonzero) digits is 9600, while the sum is 29.

The spelling of 21250640252 in words is "twenty-one billion, two hundred fifty million, six hundred forty thousand, two hundred fifty-two".