61938765649 has 2 divisors, whose sum is σ = 61938765650. Its totient is φ = 61938765648.

The previous prime is 61938765599. The next prime is 61938765677. The reversal of 61938765649 is 94656783916.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 31964076225 + 29974689424 = 178785^2 + 173132^2 .

It is a cyclic number.

It is not a de Polignac number, because 61938765649 - 2¹⁷ = 61938634577 is a prime.

It is not a weakly prime, because it can be changed into another prime (61938762649) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30969382824 + 30969382825.

It is an arithmetic number, because the mean of its divisors is an integer number (30969382825).

Almost surely, 2^61938765649 is an apocalyptic number.

It is an amenable number.

61938765649 is a deficient number, since it is larger than the sum of its proper divisors (1).

61938765649 is an equidigital number, since it uses as much as digits as its factorization.

61938765649 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 58786560, while the sum is 64.

The spelling of 61938765649 in words is "sixty-one billion, nine hundred thirty-eight million, seven hundred sixty-five thousand, six hundred forty-nine".