61672936561 has 2 divisors, whose sum is σ = 61672936562. Its totient is φ = 61672936560.

The previous prime is 61672936553. The next prime is 61672936571. The reversal of 61672936561 is 16563927616.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 58235342400 + 3437594161 = 241320^2 + 58631^2 .

It is a cyclic number.

It is not a de Polignac number, because 61672936561 - 2³ = 61672936553 is a prime.

It is a super-2 number, since 2×61672936561² (a number of 22 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 61672936499 and 61672936508.

It is not a weakly prime, because it can be changed into another prime (61672936571) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30836468280 + 30836468281.

It is an arithmetic number, because the mean of its divisors is an integer number (30836468281).

Almost surely, 2^61672936561 is an apocalyptic number.

It is an amenable number.

61672936561 is a deficient number, since it is larger than the sum of its proper divisors (1).

61672936561 is an equidigital number, since it uses as much as digits as its factorization.

61672936561 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2449440, while the sum is 52.

The spelling of 61672936561 in words is "sixty-one billion, six hundred seventy-two million, nine hundred thirty-six thousand, five hundred sixty-one".