80621784891 has 16 divisors (see below), whose sum is σ = 119542427520. Its totient is φ = 53701620840.

The previous prime is 80621784853. The next prime is 80621784911. The reversal of 80621784891 is 19848712608.

80621784891 is a `hidden beast` number, since 8 + 0 + 621 + 7 + 8 + 4 + 8 + 9 + 1 = 666.

It is not a de Polignac number, because 80621784891 - 2¹³ = 80621776699 is a prime.

It is a Smith number, since the sum of its digits (54) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (80621786891) 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, 1252345 + ... + 1315146.

It is an arithmetic number, because the mean of its divisors is an integer number (7471401720).

Almost surely, 2^80621784891 is an apocalyptic number.

80621784891 is a deficient number, since it is larger than the sum of its proper divisors (38920642629).

80621784891 is a wasteful number, since it uses less digits than its factorization.

80621784891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2568663 (or 2568657 counting only the distinct ones).

The product of its (nonzero) digits is 1548288, while the sum is 54.

The spelling of 80621784891 in words is "eighty billion, six hundred twenty-one million, seven hundred eighty-four thousand, eight hundred ninety-one".