61020472891 has 4 divisors (see below), whose sum is σ = 69737683312. Its totient is φ = 52303262472.

The previous prime is 61020472889. The next prime is 61020472907. The reversal of 61020472891 is 19827402016.

61020472891 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is not a de Polignac number, because 61020472891 - 2¹ = 61020472889 is a prime.

It is a super-2 number, since 2×61020472891² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61020472801) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4358605200 + ... + 4358605213.

It is an arithmetic number, because the mean of its divisors is an integer number (17434420828).

Almost surely, 2^61020472891 is an apocalyptic number.

61020472891 is a deficient number, since it is larger than the sum of its proper divisors (8717210421).

61020472891 is an equidigital number, since it uses as much as digits as its factorization.

61020472891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8717210420.

The product of its (nonzero) digits is 48384, while the sum is 40.

The spelling of 61020472891 in words is "sixty-one billion, twenty million, four hundred seventy-two thousand, eight hundred ninety-one".