999920203031 has 4 divisors (see below), whose sum is σ = 999941305464. Its totient is φ = 999899100600.

The previous prime is 999920203021. The next prime is 999920203049. The reversal of 999920203031 is 130302029999.

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

It is a cyclic number.

It is not a de Polignac number, because 999920203031 - 2³⁸ = 725042296087 is a prime.

It is a super-2 number, since 2×999920203031² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (999920203021) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10479980 + ... + 10574961.

It is an arithmetic number, because the mean of its divisors is an integer number (249985326366).

Almost surely, 2^999920203031 is an apocalyptic number.

999920203031 is a deficient number, since it is larger than the sum of its proper divisors (21102433).

999920203031 is a wasteful number, since it uses less digits than its factorization.

999920203031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21102432.

The product of its (nonzero) digits is 236196, while the sum is 47.

The spelling of 999920203031 in words is "nine hundred ninety-nine billion, nine hundred twenty million, two hundred three thousand, thirty-one".