61913081 has 2 divisors, whose sum is σ = 61913082. Its totient is φ = 61913080.

The previous prime is 61913069. The next prime is 61913113. The reversal of 61913081 is 18031916.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 41165056 + 20748025 = 6416^2 + 4555^2 .

It is a cyclic number.

It is not a de Polignac number, because 61913081 - 2⁶ = 61913017 is a prime.

It is a super-3 number, since 3×61913081³ (a number of 24 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (61913281) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30956540 + 30956541.

It is an arithmetic number, because the mean of its divisors is an integer number (30956541).

Almost surely, 2^61913081 is an apocalyptic number.

It is an amenable number.

61913081 is a deficient number, since it is larger than the sum of its proper divisors (1).

61913081 is an equidigital number, since it uses as much as digits as its factorization.

61913081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1296, while the sum is 29.

The square root of 61913081 is about 7868.4865762102. The cubic root of 61913081 is about 395.6041196417.

Adding to 61913081 its reverse (18031916), we get a palindrome (79944997).

The spelling of 61913081 in words is "sixty-one million, nine hundred thirteen thousand, eighty-one".