61657565 has 16 divisors (see below), whose sum is σ = 78697920. Its totient is φ = 46241280.

The previous prime is 61657559. The next prime is 61657579. The reversal of 61657565 is 56575616.

It is not a de Polignac number, because 61657565 - 2²⁴ = 44880349 is a prime.

It is a super-5 number, since 5×61657565⁵ (a number of 40 digits) contains 55555 as substring.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5870 + ... + 12560.

It is an arithmetic number, because the mean of its divisors is an integer number (4918620).

Almost surely, 2^61657565 is an apocalyptic number.

It is an amenable number.

61657565 is a deficient number, since it is larger than the sum of its proper divisors (17040355).

61657565 is a wasteful number, since it uses less digits than its factorization.

61657565 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6812.

The product of its digits is 189000, while the sum is 41.

The square root of 61657565 is about 7852.2331218578. The cubic root of 61657565 is about 395.0591483289.

The spelling of 61657565 in words is "sixty-one million, six hundred fifty-seven thousand, five hundred sixty-five".