84191770921 has 8 divisors (see below), whose sum is σ = 89147062944. Its totient is φ = 79236793920.

The previous prime is 84191770913. The next prime is 84191770933. The reversal of 84191770921 is 12907719148.

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

It is a cyclic number.

It is not a de Polignac number, because 84191770921 - 2³ = 84191770913 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (84191770951) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 680946 + ... + 795028.

It is an arithmetic number, because the mean of its divisors is an integer number (11143382868).

Almost surely, 2^84191770921 is an apocalyptic number.

It is an amenable number.

84191770921 is a deficient number, since it is larger than the sum of its proper divisors (4955292023).

84191770921 is a wasteful number, since it uses less digits than its factorization.

84191770921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 157511.

The product of its (nonzero) digits is 254016, while the sum is 49.

The spelling of 84191770921 in words is "eighty-four billion, one hundred ninety-one million, seven hundred seventy thousand, nine hundred twenty-one".