61277660561720 has 16 divisors (see below), whose sum is σ = 137874736263960. Its totient is φ = 24511064224672.

The previous prime is 61277660561713. The next prime is 61277660561801. The reversal of 61277660561720 is 2716506677216.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 765970756982 + ... + 765970757061.

Almost surely, 2^{61277660561720} is an apocalyptic number.

It is an amenable number.

61277660561720 is an abundant number, since it is smaller than the sum of its proper divisors (76597075702240).

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

61277660561720 is a wasteful number, since it uses less digits than its factorization.

61277660561720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1531941514054 (or 1531941514050 counting only the distinct ones).

The product of its (nonzero) digits is 8890560, while the sum is 56.

The spelling of 61277660561720 in words is "sixty-one trillion, two hundred seventy-seven billion, six hundred sixty million, five hundred sixty-one thousand, seven hundred twenty".