84237919821 has 24 divisors (see below), whose sum is σ = 133913235456. Its totient is φ = 50601479040.

The previous prime is 84237919807. The next prime is 84237919823. The reversal of 84237919821 is 12891973248.

84237919821 is a `hidden beast` number, since 8 + 423 + 7 + 9 + 198 + 21 = 666.

It is not a de Polignac number, because 84237919821 - 2⁷ = 84237919693 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (84237919823) 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, 3753805 + ... + 3776178.

It is an arithmetic number, because the mean of its divisors is an integer number (5579718144).

Almost surely, 2^84237919821 is an apocalyptic number.

It is an amenable number.

84237919821 is a deficient number, since it is larger than the sum of its proper divisors (49675315635).

84237919821 is a wasteful number, since it uses less digits than its factorization.

84237919821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7530113 (or 7530110 counting only the distinct ones).

The product of its digits is 1741824, while the sum is 54.

The spelling of 84237919821 in words is "eighty-four billion, two hundred thirty-seven million, nine hundred nineteen thousand, eight hundred twenty-one".