61315081 has 2 divisors, whose sum is σ = 61315082. Its totient is φ = 61315080.

The previous prime is 61315069. The next prime is 61315097. The reversal of 61315081 is 18051316.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 60140025 + 1175056 = 7755^2 + 1084^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-61315081 is a prime.

It is a super-2 number, since 2×61315081² = 7519078316073122, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (61375081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30657540 + 30657541.

It is an arithmetic number, because the mean of its divisors is an integer number (30657541).

Almost surely, 2^61315081 is an apocalyptic number.

It is an amenable number.

61315081 is a deficient number, since it is larger than the sum of its proper divisors (1).

61315081 is an equidigital number, since it uses as much as digits as its factorization.

61315081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 720, while the sum is 25.

The square root of 61315081 is about 7830.3946899246. The cubic root of 61315081 is about 394.3263227134.

Adding to 61315081 its reverse (18051316), we get a palindrome (79366397).

The spelling of 61315081 in words is "sixty-one million, three hundred fifteen thousand, eighty-one".