61212547997 has 2 divisors, whose sum is σ = 61212547998. Its totient is φ = 61212547996.

The previous prime is 61212547937. The next prime is 61212548003. The reversal of 61212547997 is 79974521216.

61212547997 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 42710835556 + 18501712441 = 206666^2 + 136021^2 .

It is a cyclic number.

It is not a de Polignac number, because 61212547997 - 2⁶ = 61212547933 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61212547927) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30606273998 + 30606273999.

It is an arithmetic number, because the mean of its divisors is an integer number (30606273999).

Almost surely, 2^61212547997 is an apocalyptic number.

It is an amenable number.

61212547997 is a deficient number, since it is larger than the sum of its proper divisors (1).

61212547997 is an equidigital number, since it uses as much as digits as its factorization.

61212547997 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1905120, while the sum is 53.

The spelling of 61212547997 in words is "sixty-one billion, two hundred twelve million, five hundred forty-seven thousand, nine hundred ninety-seven".