61512715278 has 224 divisors, whose sum is σ = 164191334400. Its totient is φ = 16905335040.

The previous prime is 61512715261. The next prime is 61512715279. The reversal of 61512715278 is 87251721516.

61512715278 is a `hidden beast` number, since 6 + 1 + 51 + 2 + 71 + 527 + 8 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61512715279) by changing a digit.

It is a polite number, since it can be written in 111 ways as a sum of consecutive naturals, for example, 62960326 + ... + 62961302.

Almost surely, 2^61512715278 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61512715278, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (82095667200).

61512715278 is an abundant number, since it is smaller than the sum of its proper divisors (102678619122).

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

61512715278 is a wasteful number, since it uses less digits than its factorization.

61512715278 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1234 (or 1219 counting only the distinct ones).

The product of its digits is 235200, while the sum is 45.

The spelling of 61512715278 in words is "sixty-one billion, five hundred twelve million, seven hundred fifteen thousand, two hundred seventy-eight".