5121991566 has 12 divisors (see below), whose sum is σ = 11097648432. Its totient is φ = 1707330516.

The previous prime is 5121991559. The next prime is 5121991573. The reversal of 5121991566 is 6651991215.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (5121991559) and next prime (5121991573).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 142277526 + ... + 142277561.

It is an arithmetic number, because the mean of its divisors is an integer number (924804036).

Almost surely, 2^5121991566 is an apocalyptic number.

5121991566 is an abundant number, since it is smaller than the sum of its proper divisors (5975656866).

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

5121991566 is a wasteful number, since it uses less digits than its factorization.

5121991566 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 284555095 (or 284555092 counting only the distinct ones).

The product of its digits is 145800, while the sum is 45.

The square root of 5121991566 is about 71568.0904174479. The cubic root of 5121991566 is about 1723.7711969562.

The spelling of 5121991566 in words is "five billion, one hundred twenty-one million, nine hundred ninety-one thousand, five hundred sixty-six".