84697904821 has 4 divisors (see below), whose sum is σ = 85052289600. Its totient is φ = 84343520044.

The previous prime is 84697904789. The next prime is 84697904843. The reversal of 84697904821 is 12840979648.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 84697904821 - 2⁵ = 84697904789 is a prime.

It is a Smith number, since the sum of its digits (58) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (84697904321) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 177192031 + ... + 177192508.

It is an arithmetic number, because the mean of its divisors is an integer number (21263072400).

Almost surely, 2^84697904821 is an apocalyptic number.

It is an amenable number.

84697904821 is a deficient number, since it is larger than the sum of its proper divisors (354384779).

84697904821 is a wasteful number, since it uses less digits than its factorization.

84697904821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 354384778.

The product of its (nonzero) digits is 6967296, while the sum is 58.

The spelling of 84697904821 in words is "eighty-four billion, six hundred ninety-seven million, nine hundred four thousand, eight hundred twenty-one".