61272981 has 72 divisors (see below), whose sum is σ = 119081664. Its totient is φ = 29917440.

The previous prime is 61272977. The next prime is 61272997. The reversal of 61272981 is 18927216.

It is not a de Polignac number, because 61272981 - 2² = 61272977 is a prime.

It is a super-2 number, since 2×61272981² = 7508756401252722, which contains 22 as substring.

It is an alternating number because its digits alternate between even and odd.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61272961) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 82096 + ... + 82838.

It is an arithmetic number, because the mean of its divisors is an integer number (1653912).

Almost surely, 2^61272981 is an apocalyptic number.

It is an amenable number.

61272981 is a deficient number, since it is larger than the sum of its proper divisors (57808683).

61272981 is a wasteful number, since it uses less digits than its factorization.

61272981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 791 (or 781 counting only the distinct ones).

The product of its digits is 12096, while the sum is 36.

The square root of 61272981 is about 7827.7059857918. The cubic root of 61272981 is about 394.2360516147.

The spelling of 61272981 in words is "sixty-one million, two hundred seventy-two thousand, nine hundred eighty-one".