491553879870 has 64 divisors (see below), whose sum is σ = 1289419554816. Its totient is φ = 119390691840.

The previous prime is 491553879829. The next prime is 491553879917. The reversal of 491553879870 is 78978355194.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 15529854 + ... + 15561473.

It is an arithmetic number, because the mean of its divisors is an integer number (20147180544).

Almost surely, 2^491553879870 is an apocalyptic number.

491553879870 is an abundant number, since it is smaller than the sum of its proper divisors (797865674946).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

491553879870 is a wasteful number, since it uses less digits than its factorization.

491553879870 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31091385.

The product of its (nonzero) digits is 76204800, while the sum is 66.

The spelling of 491553879870 in words is "four hundred ninety-one billion, five hundred fifty-three million, eight hundred seventy-nine thousand, eight hundred seventy".