61305991097 has 16 divisors (see below), whose sum is σ = 68584320000. Its totient is φ = 54410067264.

The previous prime is 61305991069. The next prime is 61305991151. The reversal of 61305991097 is 79019950316.

It is not a de Polignac number, because 61305991097 - 2⁸ = 61305990841 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61305991007) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 250097 + ... + 430302.

It is an arithmetic number, because the mean of its divisors is an integer number (4286520000).

Almost surely, 2^61305991097 is an apocalyptic number.

It is an amenable number.

61305991097 is a deficient number, since it is larger than the sum of its proper divisors (7278328903).

61305991097 is a wasteful number, since it uses less digits than its factorization.

61305991097 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 680680.

The product of its (nonzero) digits is 459270, while the sum is 50.

The spelling of 61305991097 in words is "sixty-one billion, three hundred five million, nine hundred ninety-one thousand, ninety-seven".