61520179999 has 2 divisors, whose sum is σ = 61520180000. Its totient is φ = 61520179998.

The previous prime is 61520179907. The next prime is 61520180027. The reversal of 61520179999 is 99997102516.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 61520179999 - 2²⁷ = 61385962271 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61520179199) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30760089999 + 30760090000.

It is an arithmetic number, because the mean of its divisors is an integer number (30760090000).

Almost surely, 2^61520179999 is an apocalyptic number.

61520179999 is a deficient number, since it is larger than the sum of its proper divisors (1).

61520179999 is an equidigital number, since it uses as much as digits as its factorization.

61520179999 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2755620, while the sum is 58.

The spelling of 61520179999 in words is "sixty-one billion, five hundred twenty million, one hundred seventy-nine thousand, nine hundred ninety-nine".