84400900821 has 24 divisors (see below), whose sum is σ = 124764484416. Its totient is φ = 54951281280.

The previous prime is 84400900811. The next prime is 84400900823. The reversal of 84400900821 is 12800900448.

It is not a de Polignac number, because 84400900821 - 2¹⁵ = 84400868053 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (84400900823) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 5574141 + ... + 5589261.

It is an arithmetic number, because the mean of its divisors is an integer number (5198520184).

Almost surely, 2^84400900821 is an apocalyptic number.

It is an amenable number.

84400900821 is a deficient number, since it is larger than the sum of its proper divisors (40363583595).

84400900821 is a wasteful number, since it uses less digits than its factorization.

84400900821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29593 (or 29590 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 36.

The spelling of 84400900821 in words is "eighty-four billion, four hundred million, nine hundred thousand, eight hundred twenty-one".