61988161 has 2 divisors, whose sum is σ = 61988162. Its totient is φ = 61988160.

The previous prime is 61988131. The next prime is 61988177. The reversal of 61988161 is 16188916.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 61074225 + 913936 = 7815^2 + 956^2 .

It is a cyclic number.

It is not a de Polignac number, because 61988161 - 2⁹ = 61987649 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (61988131) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30994080 + 30994081.

It is an arithmetic number, because the mean of its divisors is an integer number (30994081).

Almost surely, 2^61988161 is an apocalyptic number.

It is an amenable number.

61988161 is a deficient number, since it is larger than the sum of its proper divisors (1).

61988161 is an equidigital number, since it uses as much as digits as its factorization.

61988161 is an evil number, because the sum of its binary digits is even.

The product of its digits is 20736, while the sum is 40.

The square root of 61988161 is about 7873.2560608683. The cubic root of 61988161 is about 395.7639671715.

The spelling of 61988161 in words is "sixty-one million, nine hundred eighty-eight thousand, one hundred sixty-one".