61557389399 has 16 divisors (see below), whose sum is σ = 68990472576. Its totient is φ = 54431431200.

The previous prime is 61557389389. The next prime is 61557389401. The reversal of 61557389399 is 99398375516.

It is a cyclic number.

It is not a de Polignac number, because 61557389399 - 2³² = 57262422103 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61557389339) 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 in 15 ways as a sum of consecutive naturals, for example, 1349564 + ... + 1394430.

It is an arithmetic number, because the mean of its divisors is an integer number (4311904536).

Almost surely, 2^61557389399 is an apocalyptic number.

61557389399 is a deficient number, since it is larger than the sum of its proper divisors (7433083177).

61557389399 is a wasteful number, since it uses less digits than its factorization.

61557389399 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48286.

The product of its digits is 55112400, while the sum is 65.

The spelling of 61557389399 in words is "sixty-one billion, five hundred fifty-seven million, three hundred eighty-nine thousand, three hundred ninety-nine".