21325051 has 12 divisors (see below), whose sum is σ = 23696712. Its totient is φ = 19032000.

The previous prime is 21325037. The next prime is 21325093. The reversal of 21325051 is 15052312.

21325051 = 561² + 562² + ... + 621².

It is not a de Polignac number, because 21325051 - 2⁷ = 21324923 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21325151) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 40671 + ... + 41191.

It is an arithmetic number, because the mean of its divisors is an integer number (1974726).

Almost surely, 2^21325051 is an apocalyptic number.

21325051 is a deficient number, since it is larger than the sum of its proper divisors (2371661).

21325051 is an equidigital number, since it uses as much as digits as its factorization.

21325051 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 654 (or 593 counting only the distinct ones).

The product of its (nonzero) digits is 300, while the sum is 19.

The square root of 21325051 is about 4617.9054775948. The cubic root of 21325051 is about 277.3086135370.

Adding to 21325051 its reverse (15052312), we get a palindrome (36377363).

The spelling of 21325051 in words is "twenty-one million, three hundred twenty-five thousand, fifty-one".