61878861 has 24 divisors (see below), whose sum is σ = 103244544. Its totient is φ = 35295360.

The previous prime is 61878857. The next prime is 61878863. The reversal of 61878861 is 16887816.

It is not a de Polignac number, because 61878861 - 2² = 61878857 is a prime.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61878863) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 16701 + ... + 20066.

It is an arithmetic number, because the mean of its divisors is an integer number (4301856).

Almost surely, 2^61878861 is an apocalyptic number.

It is an amenable number.

61878861 is a deficient number, since it is larger than the sum of its proper divisors (41365683).

61878861 is a wasteful number, since it uses less digits than its factorization.

61878861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36801 (or 36798 counting only the distinct ones).

The product of its digits is 129024, while the sum is 45.

The square root of 61878861 is about 7866.3117787182. The cubic root of 61878861 is about 395.5312213804.

The spelling of 61878861 in words is "sixty-one million, eight hundred seventy-eight thousand, eight hundred sixty-one".