61235956681 has 9 divisors (see below), whose sum is σ = 61739658823. Its totient is φ = 60736336960.

The previous prime is 61235956657. The next prime is 61235956693. The reversal of 61235956681 is 18665953216.

The square root of 61235956681 is 247459.

It is a perfect power (a square), and thus also a powerful number.

61235956681 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 29494971081 + 31740985600 = 171741^2 + 178160^2 .

It is a de Polignac number, because none of the positive numbers 2^k-61235956681 is a prime.

It is a super-2 number, since 2×61235956681² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61235156681) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 32416185 + ... + 32418073.

Almost surely, 2^61235956681 is an apocalyptic number.

61235956681 is the 247459-th square number.

61235956681 is the 123730-th centered octagonal number.

It is an amenable number.

61235956681 is a deficient number, since it is larger than the sum of its proper divisors (503702142).

61235956681 is an frugal number, since it uses more digits than its factorization.

61235956681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4040 (or 2020 counting only the distinct ones).

The product of its digits is 2332800, while the sum is 52.

The spelling of 61235956681 in words is "sixty-one billion, two hundred thirty-five million, nine hundred fifty-six thousand, six hundred eighty-one".