21355024125 has 32 divisors (see below), whose sum is σ = 35563132800. Its totient is φ = 11380252800.

The previous prime is 21355024123. The next prime is 21355024189. The reversal of 21355024125 is 52142055312.

It is not a de Polignac number, because 21355024125 - 2¹ = 21355024123 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21355024092 and 21355024101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21355024123) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 461286 + ... + 505464.

It is an arithmetic number, because the mean of its divisors is an integer number (1111347900).

Almost surely, 2^21355024125 is an apocalyptic number.

21355024125 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21355024125 is a deficient number, since it is larger than the sum of its proper divisors (14208108675).

21355024125 is a wasteful number, since it uses less digits than its factorization.

21355024125 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45486 (or 45476 counting only the distinct ones).

The product of its (nonzero) digits is 12000, while the sum is 30.

Adding to 21355024125 its reverse (52142055312), we get a palindrome (73497079437).

The spelling of 21355024125 in words is "twenty-one billion, three hundred fifty-five million, twenty-four thousand, one hundred twenty-five".