21013304425 has 24 divisors (see below), whose sum is σ = 26262897440. Its totient is φ = 16677964800.

The previous prime is 21013304407. The next prime is 21013304437. The reversal of 21013304425 is 52440331012.

It is a de Polignac number, because none of the positive numbers 2^k-21013304425 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (25).

It is a self number, because there is not a number n which added to its sum of digits gives 21013304425.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1822930 + ... + 1834420.

Almost surely, 2^21013304425 is an apocalyptic number.

21013304425 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21013304425 is a deficient number, since it is larger than the sum of its proper divisors (5249593015).

21013304425 is a wasteful number, since it uses less digits than its factorization.

21013304425 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12073 (or 12068 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 25.

Adding to 21013304425 its reverse (52440331012), we get a palindrome (73453635437).

The spelling of 21013304425 in words is "twenty-one billion, thirteen million, three hundred four thousand, four hundred twenty-five".