64861770721191 has 8 divisors (see below), whose sum is σ = 86930456096880. Its totient is φ = 43017132913152.

The previous prime is 64861770721183. The next prime is 64861770721207. The reversal of 64861770721191 is 19112707716846.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 64861770721191 - 2³ = 64861770721183 is a prime.

It is a Smith number, since the sum of its digits (60) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64861770721151) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (31) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 56011891236 + ... + 56011892393.

It is an arithmetic number, because the mean of its divisors is an integer number (10866307012110).

Almost surely, 2^{64861770721191} is an apocalyptic number.

64861770721191 is a deficient number, since it is larger than the sum of its proper divisors (22068685375689).

64861770721191 is a wasteful number, since it uses less digits than its factorization.

64861770721191 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 112023783825.

The product of its (nonzero) digits is 7112448, while the sum is 60.

The spelling of 64861770721191 in words is "sixty-four trillion, eight hundred sixty-one billion, seven hundred seventy million, seven hundred twenty-one thousand, one hundred ninety-one".