21250251640120 has 32 divisors (see below), whose sum is σ = 50625599497200. Its totient is φ = 8000094734848.

The previous prime is 21250251640099. The next prime is 21250251640127. The reversal of 21250251640120 is 2104615205212.

It is a super-2 number, since 2×21250251640120² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21250251640127) 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, 15625184350 + ... + 15625185709.

Almost surely, 2^{21250251640120} is an apocalyptic number.

21250251640120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21250251640120 is an abundant number, since it is smaller than the sum of its proper divisors (29375347857080).

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

21250251640120 is a wasteful number, since it uses less digits than its factorization.

21250251640120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31250370087 (or 31250370083 counting only the distinct ones).

The product of its (nonzero) digits is 9600, while the sum is 31.

Adding to 21250251640120 its reverse (2104615205212), we get a palindrome (23354866845332).

The spelling of 21250251640120 in words is "twenty-one trillion, two hundred fifty billion, two hundred fifty-one million, six hundred forty thousand, one hundred twenty".