61931887 has 16 divisors (see below), whose sum is σ = 67075200. Its totient is φ = 57002400.

The previous prime is 61931879. The next prime is 61931923. The reversal of 61931887 is 78813916.

61931887 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 61931887 - 2³ = 61931879 is a prime.

It is a super-5 number, since 5×61931887⁵ (a number of 40 digits) contains 55555 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61931827) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 112948 + ... + 113494.

It is an arithmetic number, because the mean of its divisors is an integer number (4192200).

Almost surely, 2^61931887 is an apocalyptic number.

61931887 is a deficient number, since it is larger than the sum of its proper divisors (5143313).

61931887 is a wasteful number, since it uses less digits than its factorization.

61931887 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 726.

The product of its digits is 72576, while the sum is 43.

The square root of 61931887 is about 7869.6815056265. The cubic root of 61931887 is about 395.6441702945.

The spelling of 61931887 in words is "sixty-one million, nine hundred thirty-one thousand, eight hundred eighty-seven".