990799993 has 4 divisors (see below), whose sum is σ = 1024965540. Its totient is φ = 956634448.

The previous prime is 990799987. The next prime is 990800033. The reversal of 990799993 is 399997099.

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 391921209 + 598878784 = 19797^2 + 24472^2 .

It is a cyclic number.

It is not a de Polignac number, because 990799993 - 2¹³ = 990791801 is a prime.

It is a super-2 number, since 2×990799993² = 1963369252257600098, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (990799493) 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, 17082730 + ... + 17082787.

It is an arithmetic number, because the mean of its divisors is an integer number (256241385).

Almost surely, 2^990799993 is an apocalyptic number.

It is an amenable number.

990799993 is a deficient number, since it is larger than the sum of its proper divisors (34165547).

990799993 is a wasteful number, since it uses less digits than its factorization.

990799993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34165546.

The product of its (nonzero) digits is 11160261, while the sum is 64.

The square root of 990799993 is about 31476.9756012232. The cubic root of 990799993 is about 996.9238781772.

The spelling of 990799993 in words is "nine hundred ninety million, seven hundred ninety-nine thousand, nine hundred ninety-three".