65625551 has 4 divisors (see below), whose sum is σ = 65662392. Its totient is φ = 65588712.

The previous prime is 65625503. The next prime is 65625557. The reversal of 65625551 is 15552656.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 65625551 - 2¹⁰ = 65624527 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65625557) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15605 + ... + 19358.

It is an arithmetic number, because the mean of its divisors is an integer number (16415598).

Almost surely, 2^65625551 is an apocalyptic number.

65625551 is a deficient number, since it is larger than the sum of its proper divisors (36841).

65625551 is a wasteful number, since it uses less digits than its factorization.

65625551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36840.

The product of its digits is 45000, while the sum is 35.

The square root of 65625551 is about 8100.9598813968. The cubic root of 65625551 is about 403.3582903908.

The spelling of 65625551 in words is "sixty-five million, six hundred twenty-five thousand, five hundred fifty-one".