61455978 has 24 divisors (see below), whose sum is σ = 135989568. Its totient is φ = 20049192.

The previous prime is 61455971. The next prime is 61456019. The reversal of 61455978 is 87955416.

It is not an unprimeable number, because it can be changed into a prime (61455971) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 35476 + ... + 37167.

It is an arithmetic number, because the mean of its divisors is an integer number (5666232).

Almost surely, 2^61455978 is an apocalyptic number.

61455978 is an abundant number, since it is smaller than the sum of its proper divisors (74533590).

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

61455978 is a wasteful number, since it uses less digits than its factorization.

61455978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72698 (or 72695 counting only the distinct ones).

The product of its digits is 302400, while the sum is 45.

The square root of 61455978 is about 7839.3863280234. The cubic root of 61455978 is about 394.6281347758.

The spelling of 61455978 in words is "sixty-one million, four hundred fifty-five thousand, nine hundred seventy-eight".