21125010502 has 32 divisors (see below), whose sum is σ = 35307993600. Its totient is φ = 9436821408.

The previous prime is 21125010497. The next prime is 21125010539. The reversal of 21125010502 is 20501052112.

It is a super-2 number, since 2×21125010502² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (19).

It is a self number, because there is not a number n which added to its sum of digits gives 21125010502.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 175518 + ... + 270289.

It is an arithmetic number, because the mean of its divisors is an integer number (1103374800).

Almost surely, 2^21125010502 is an apocalyptic number.

21125010502 is a deficient number, since it is larger than the sum of its proper divisors (14182983098).

21125010502 is a wasteful number, since it uses less digits than its factorization.

21125010502 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 445900.

The product of its (nonzero) digits is 200, while the sum is 19.

Adding to 21125010502 its reverse (20501052112), we get a palindrome (41626062614).

The spelling of 21125010502 in words is "twenty-one billion, one hundred twenty-five million, ten thousand, five hundred two".