61461220521 has 16 divisors (see below), whose sum is σ = 88614929664. Its totient is φ = 37743393024.

The previous prime is 61461220493. The next prime is 61461220547. The reversal of 61461220521 is 12502216416.

It is not a de Polignac number, because 61461220521 - 2⁷ = 61461220393 is a prime.

It is a super-2 number, since 2×61461220521² (a number of 22 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (61461220021) 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, 12818050 + ... + 12822843.

It is an arithmetic number, because the mean of its divisors is an integer number (5538433104).

Almost surely, 2^61461220521 is an apocalyptic number.

It is an amenable number.

61461220521 is a deficient number, since it is larger than the sum of its proper divisors (27153709143).

61461220521 is a wasteful number, since it uses less digits than its factorization.

61461220521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25640960.

The product of its (nonzero) digits is 5760, while the sum is 30.

Adding to 61461220521 its reverse (12502216416), we get a palindrome (73963436937).

The spelling of 61461220521 in words is "sixty-one billion, four hundred sixty-one million, two hundred twenty thousand, five hundred twenty-one".