61916381 has 2 divisors, whose sum is σ = 61916382. Its totient is φ = 61916380.

The previous prime is 61916377. The next prime is 61916411. The reversal of 61916381 is 18361916.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 55741156 + 6175225 = 7466^2 + 2485^2 .

It is a cyclic number.

It is not a de Polignac number, because 61916381 - 2² = 61916377 is a prime.

It is a super-2 number, since 2×61916381² = 7667276472274322, which contains 22 as substring.

It is equal to p_3668912 and since 61916381 and 3668912 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61916341) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30958190 + 30958191.

It is an arithmetic number, because the mean of its divisors is an integer number (30958191).

Almost surely, 2^61916381 is an apocalyptic number.

It is an amenable number.

61916381 is a deficient number, since it is larger than the sum of its proper divisors (1).

61916381 is an equidigital number, since it uses as much as digits as its factorization.

61916381 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7776, while the sum is 35.

The square root of 61916381 is about 7868.6962706664. The cubic root of 61916381 is about 395.6111481532.

The spelling of 61916381 in words is "sixty-one million, nine hundred sixteen thousand, three hundred eighty-one".