61656513 has 4 divisors (see below), whose sum is σ = 82208688. Its totient is φ = 41104340.

The previous prime is 61656499. The next prime is 61656533. The reversal of 61656513 is 31565616.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 61656513 - 2⁵ = 61656481 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (61656533) 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, 10276083 + ... + 10276088.

It is an arithmetic number, because the mean of its divisors is an integer number (20552172).

Almost surely, 2^61656513 is an apocalyptic number.

It is an amenable number.

61656513 is a deficient number, since it is larger than the sum of its proper divisors (20552175).

61656513 is a wasteful number, since it uses less digits than its factorization.

61656513 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20552174.

The product of its digits is 16200, while the sum is 33.

The square root of 61656513 is about 7852.1661342587. The cubic root of 61656513 is about 395.0569014860.

The spelling of 61656513 in words is "sixty-one million, six hundred fifty-six thousand, five hundred thirteen".