61318223957 has 2 divisors, whose sum is σ = 61318223958. Its totient is φ = 61318223956.

The previous prime is 61318223921. The next prime is 61318223977. The reversal of 61318223957 is 75932281316.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 54174424516 + 7143799441 = 232754^2 + 84521^2 .

It is a cyclic number.

It is not a de Polignac number, because 61318223957 - 2⁶ = 61318223893 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61318223977) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30659111978 + 30659111979.

It is an arithmetic number, because the mean of its divisors is an integer number (30659111979).

Almost surely, 2^61318223957 is an apocalyptic number.

It is an amenable number.

61318223957 is a deficient number, since it is larger than the sum of its proper divisors (1).

61318223957 is an equidigital number, since it uses as much as digits as its factorization.

61318223957 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 544320, while the sum is 47.

The spelling of 61318223957 in words is "sixty-one billion, three hundred eighteen million, two hundred twenty-three thousand, nine hundred fifty-seven".