623920993 has 24 divisors (see below), whose sum is σ = 693069480. Its totient is φ = 560770560.

The previous prime is 623920987. The next prime is 623921003. The reversal of 623920993 is 399029326.

It can be written as a sum of positive squares in 4 ways, for example, as 80425024 + 543495969 = 8968^2 + 23313^2 .

It is not a de Polignac number, because 623920993 - 2⁹ = 623920481 is a prime.

It is a super-2 number, since 2×623920993² = 778554811012212098, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (623920933) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 638121 + ... + 639097.

It is an arithmetic number, because the mean of its divisors is an integer number (28877895).

Almost surely, 2^623920993 is an apocalyptic number.

It is an amenable number.

623920993 is a deficient number, since it is larger than the sum of its proper divisors (69148487).

623920993 is a wasteful number, since it uses less digits than its factorization.

623920993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1105 (or 1086 counting only the distinct ones).

The product of its (nonzero) digits is 157464, while the sum is 43.

The square root of 623920993 is about 24978.4105379025. The cubic root of 623920993 is about 854.4956696524.

The spelling of 623920993 in words is "six hundred twenty-three million, nine hundred twenty thousand, nine hundred ninety-three".