61643659 has 16 divisors (see below), whose sum is σ = 77068800. Its totient is φ = 47900160.

The previous prime is 61643653. The next prime is 61643669. The reversal of 61643659 is 95634616.

It is not a de Polignac number, because 61643659 - 2³ = 61643651 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61643651) 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, 33682 + ... + 35464.

It is an arithmetic number, because the mean of its divisors is an integer number (4816800).

Almost surely, 2^61643659 is an apocalyptic number.

61643659 is a deficient number, since it is larger than the sum of its proper divisors (15425141).

61643659 is a wasteful number, since it uses less digits than its factorization.

61643659 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2250.

The product of its digits is 116640, while the sum is 40.

The square root of 61643659 is about 7851.3475913374. The cubic root of 61643659 is about 395.0294460770.

The spelling of 61643659 in words is "sixty-one million, six hundred forty-three thousand, six hundred fifty-nine".