65725521 has 16 divisors (see below), whose sum is σ = 89136000. Its totient is φ = 43072128.

The previous prime is 65725511. The next prime is 65725529. The reversal of 65725521 is 12552756.

It is not a de Polignac number, because 65725521 - 2⁵ = 65725489 is a prime.

It is a super-2 number, since 2×65725521² = 8639688221442882, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (65725529) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 52515 + ... + 53751.

It is an arithmetic number, because the mean of its divisors is an integer number (5571000).

Almost surely, 2^65725521 is an apocalyptic number.

It is an amenable number.

65725521 is a deficient number, since it is larger than the sum of its proper divisors (23410479).

65725521 is a wasteful number, since it uses less digits than its factorization.

65725521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1528.

The product of its digits is 21000, while the sum is 33.

The square root of 65725521 is about 8107.1277897909. The cubic root of 65725521 is about 403.5630036944.

The spelling of 65725521 in words is "sixty-five million, seven hundred twenty-five thousand, five hundred twenty-one".