61643886 has 16 divisors (see below), whose sum is σ = 125128704. Its totient is φ = 20241144.

The previous prime is 61643867. The next prime is 61643891. The reversal of 61643886 is 68834616.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 76270 + ... + 77073.

It is an arithmetic number, because the mean of its divisors is an integer number (7820544).

Almost surely, 2^61643886 is an apocalyptic number.

61643886 is an abundant number, since it is smaller than the sum of its proper divisors (63484818).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

61643886 is a wasteful number, since it uses less digits than its factorization.

61643886 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 153415.

The product of its digits is 165888, while the sum is 42.

The square root of 61643886 is about 7851.3620474412. The cubic root of 61643886 is about 395.0299309691.

The spelling of 61643886 in words is "sixty-one million, six hundred forty-three thousand, eight hundred eighty-six".