99642873421 has 48 divisors (see below), whose sum is σ = 134949077760. Its totient is φ = 72669985920.

The previous prime is 99642873391. The next prime is 99642873457. The reversal of 99642873421 is 12437824699.

It is not a de Polignac number, because 99642873421 - 2⁷ = 99642873293 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (99642877421) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 336556 + ... + 559066.

It is an arithmetic number, because the mean of its divisors is an integer number (2811439120).

Almost surely, 2^99642873421 is an apocalyptic number.

99642873421 is a gapful number since it is divisible by the number (91) formed by its first and last digit.

It is an amenable number.

99642873421 is a deficient number, since it is larger than the sum of its proper divisors (35306204339).

99642873421 is a wasteful number, since it uses less digits than its factorization.

99642873421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 222594 (or 222587 counting only the distinct ones).

The product of its digits is 5225472, while the sum is 55.

The spelling of 99642873421 in words is "ninety-nine billion, six hundred forty-two million, eight hundred seventy-three thousand, four hundred twenty-one".