65661525 has 18 divisors (see below), whose sum is σ = 117607490. Its totient is φ = 35019360.

The previous prime is 65661517. The next prime is 65661611. The reversal of 65661525 is 52516656.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 2916 + 65658609 = 54^2 + 8103^2 .

It is not a de Polignac number, because 65661525 - 2³ = 65661517 is a prime.

It is a super-2 number, since 2×65661525² = 8622871730651250, which contains 22 as substring.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 65661525.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 145690 + ... + 146139.

Almost surely, 2^65661525 is an apocalyptic number.

It is an amenable number.

65661525 is a deficient number, since it is larger than the sum of its proper divisors (51945965).

65661525 is a wasteful number, since it uses less digits than its factorization.

65661525 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 291845 (or 291837 counting only the distinct ones).

The product of its digits is 54000, while the sum is 36.

The square root of 65661525 is about 8103.1799313603. The cubic root of 65661525 is about 403.4319799844.

The spelling of 65661525 in words is "sixty-five million, six hundred sixty-one thousand, five hundred twenty-five".