84915834921 has 20 divisors (see below), whose sum is σ = 134311322772. Its totient is φ = 53280523008.

The previous prime is 84915834919. The next prime is 84915834943. The reversal of 84915834921 is 12943851948.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 62582026896 + 22333808025 = 250164^2 + 149445^2 .

It is not a de Polignac number, because 84915834921 - 2¹ = 84915834919 is a prime.

It is not an unprimeable number, because it can be changed into a prime (84915834121) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 30832260 + ... + 30835013.

Almost surely, 2^84915834921 is an apocalyptic number.

84915834921 is a gapful number since it is divisible by the number (81) formed by its first and last digit.

It is an amenable number.

84915834921 is a deficient number, since it is larger than the sum of its proper divisors (49395487851).

84915834921 is a wasteful number, since it uses less digits than its factorization.

84915834921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 61667302 (or 61667293 counting only the distinct ones).

The product of its digits is 2488320, while the sum is 54.

The spelling of 84915834921 in words is "eighty-four billion, nine hundred fifteen million, eight hundred thirty-four thousand, nine hundred twenty-one".