61720072356 has 48 divisors (see below), whose sum is σ = 148764123648. Its totient is φ = 19895635200.

The previous prime is 61720072343. The next prime is 61720072357. The reversal of 61720072356 is 65327002716.

61720072356 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not an unprimeable number, because it can be changed into a prime (61720072357) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 475186 + ... + 590966.

It is an arithmetic number, because the mean of its divisors is an integer number (3099252576).

Almost surely, 2^61720072356 is an apocalyptic number.

It is an amenable number.

61720072356 is an abundant number, since it is smaller than the sum of its proper divisors (87044051292).

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

61720072356 is a wasteful number, since it uses less digits than its factorization.

61720072356 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 117252 (or 117250 counting only the distinct ones).

The product of its (nonzero) digits is 105840, while the sum is 39.

The spelling of 61720072356 in words is "sixty-one billion, seven hundred twenty million, seventy-two thousand, three hundred fifty-six".