99439854421 has 4 divisors (see below), whose sum is σ = 102127418092. Its totient is φ = 96752290752.

The previous prime is 99439854407. The next prime is 99439854443. The reversal of 99439854421 is 12445893499.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 85840796196 + 13599058225 = 292986^2 + 116615^2 .

It is a cyclic number.

It is not a de Polignac number, because 99439854421 - 2⁵ = 99439854389 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (99439854461) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1343781780 + ... + 1343781853.

It is an arithmetic number, because the mean of its divisors is an integer number (25531854523).

Almost surely, 2^99439854421 is an apocalyptic number.

It is an amenable number.

99439854421 is a deficient number, since it is larger than the sum of its proper divisors (2687563671).

99439854421 is a wasteful number, since it uses less digits than its factorization.

99439854421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2687563670.

The product of its digits is 11197440, while the sum is 58.

The spelling of 99439854421 in words is "ninety-nine billion, four hundred thirty-nine million, eight hundred fifty-four thousand, four hundred twenty-one".