61579315921 has 8 divisors (see below), whose sum is σ = 62687584800. Its totient is φ = 60473198880.

The previous prime is 61579315873. The next prime is 61579315991. The reversal of 61579315921 is 12951397516.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 61579315921 - 2¹³ = 61579307729 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61579315991) 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 7 ways as a sum of consecutive naturals, for example, 480156 + ... + 594733.

It is an arithmetic number, because the mean of its divisors is an integer number (7835948100).

Almost surely, 2^61579315921 is an apocalyptic number.

It is an amenable number.

61579315921 is a deficient number, since it is larger than the sum of its proper divisors (1108268879).

61579315921 is a wasteful number, since it uses less digits than its factorization.

61579315921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1075919.

The product of its digits is 510300, while the sum is 49.

The spelling of 61579315921 in words is "sixty-one billion, five hundred seventy-nine million, three hundred fifteen thousand, nine hundred twenty-one".