61620291889 has 4 divisors (see below), whose sum is σ = 66360314356. Its totient is φ = 56880269424.

The previous prime is 61620291857. The next prime is 61620291899. The reversal of 61620291889 is 98819202616.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 3426931600 + 58193360289 = 58540^2 + 241233^2 .

It is a cyclic number.

It is not a de Polignac number, because 61620291889 - 2⁵ = 61620291857 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61620291809) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2370011214 + ... + 2370011239.

It is an arithmetic number, because the mean of its divisors is an integer number (16590078589).

Almost surely, 2^61620291889 is an apocalyptic number.

It is an amenable number.

61620291889 is a deficient number, since it is larger than the sum of its proper divisors (4740022467).

61620291889 is a wasteful number, since it uses less digits than its factorization.

61620291889 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4740022466.

The product of its (nonzero) digits is 746496, while the sum is 52.

The spelling of 61620291889 in words is "sixty-one billion, six hundred twenty million, two hundred ninety-one thousand, eight hundred eighty-nine".