99642321605 has 8 divisors (see below), whose sum is σ = 119592650232. Its totient is φ = 79699281088.

The previous prime is 99642321593. The next prime is 99642321707. The reversal of 99642321605 is 50612324699.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 46610219236 + 53032102369 = 215894^2 + 230287^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 99642321605 - 2⁴ = 99642321589 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 99642321605.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1791902 + ... + 1846671.

It is an arithmetic number, because the mean of its divisors is an integer number (14949081279).

Almost surely, 2^99642321605 is an apocalyptic number.

It is an amenable number.

99642321605 is a deficient number, since it is larger than the sum of its proper divisors (19950328627).

99642321605 is a wasteful number, since it uses less digits than its factorization.

99642321605 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3644055.

The product of its (nonzero) digits is 699840, while the sum is 47.

The spelling of 99642321605 in words is "ninety-nine billion, six hundred forty-two million, three hundred twenty-one thousand, six hundred five".