616721589081 has 12 divisors (see below), whose sum is σ = 959344694308. Its totient is φ = 379520977824.

The previous prime is 616721589007. The next prime is 616721589089. The reversal of 616721589081 is 180985127616.

It is a happy number.

616721589081 is a `hidden beast` number, since 616 + 7 + 2 + 15 + 8 + 9 + 0 + 8 + 1 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 341874090000 + 274847499081 = 584700^2 + 524259^2 .

It is not a de Polignac number, because 616721589081 - 2²⁹ = 616184718169 is a prime.

It is a super-2 number, since 2×616721589081² (a number of 24 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (616721589089) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2635562230 + ... + 2635562463.

Almost surely, 2^616721589081 is an apocalyptic number.

It is an amenable number.

616721589081 is a deficient number, since it is larger than the sum of its proper divisors (342623105227).

616721589081 is a wasteful number, since it uses less digits than its factorization.

616721589081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5271124712 (or 5271124709 counting only the distinct ones).

The product of its (nonzero) digits is 1451520, while the sum is 54.

The spelling of 616721589081 in words is "six hundred sixteen billion, seven hundred twenty-one million, five hundred eighty-nine thousand, eighty-one".