61513160021 has 8 divisors (see below), whose sum is σ = 63748564920. Its totient is φ = 59285372608.

The previous prime is 61513159997. The next prime is 61513160039. The reversal of 61513160021 is 12006131516.

61513160021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 65691025 + 61447468996 = 8105^2 + 247886^2 .

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 61513160021 - 2⁶ = 61513159957 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 (61513160521) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1887926 + ... + 1920231.

It is an arithmetic number, because the mean of its divisors is an integer number (7968570615).

Almost surely, 2^61513160021 is an apocalyptic number.

It is an amenable number.

61513160021 is a deficient number, since it is larger than the sum of its proper divisors (2235404899).

61513160021 is a wasteful number, since it uses less digits than its factorization.

61513160021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3808743.

The product of its (nonzero) digits is 1080, while the sum is 26.

Adding to 61513160021 its reverse (12006131516), we get a palindrome (73519291537).

The spelling of 61513160021 in words is "sixty-one billion, five hundred thirteen million, one hundred sixty thousand, twenty-one".