61370728581 has 8 divisors (see below), whose sum is σ = 85385361600. Its totient is φ = 39134957312.

The previous prime is 61370728511. The next prime is 61370728583. The reversal of 61370728581 is 18582707316.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-61370728581 is a prime.

It is a super-2 number, since 2×61370728581² (a number of 22 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 61370728581.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61370728583) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 444715356 + ... + 444715493.

It is an arithmetic number, because the mean of its divisors is an integer number (10673170200).

Almost surely, 2^61370728581 is an apocalyptic number.

It is an amenable number.

61370728581 is a deficient number, since it is larger than the sum of its proper divisors (24014633019).

61370728581 is a wasteful number, since it uses less digits than its factorization.

61370728581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 889430875.

The product of its (nonzero) digits is 564480, while the sum is 48.

The spelling of 61370728581 in words is "sixty-one billion, three hundred seventy million, seven hundred twenty-eight thousand, five hundred eighty-one".