19902923 has 4 divisors (see below), whose sum is σ = 19936320. Its totient is φ = 19869528.

The previous prime is 19902913. The next prime is 19902947. The reversal of 19902923 is 32920991.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 32920991 = 41 ⋅802951.

It is a cyclic number.

It is not a de Polignac number, because 19902923 - 2¹⁸ = 19640779 is a prime.

It is a super-2 number, since 2×19902923² = 792252687887858, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19902913) 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, 15788 + ... + 17001.

It is an arithmetic number, because the mean of its divisors is an integer number (4984080).

Almost surely, 2^19902923 is an apocalyptic number.

19902923 is a deficient number, since it is larger than the sum of its proper divisors (33397).

19902923 is an equidigital number, since it uses as much as digits as its factorization.

19902923 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33396.

The product of its (nonzero) digits is 8748, while the sum is 35.

The square root of 19902923 is about 4461.2692140242. The cubic root of 19902923 is about 271.0018699689.

It can be divided in two parts, 1990 and 2923, that added together give a cube (4913 = 17³).

The spelling of 19902923 in words is "nineteen million, nine hundred two thousand, nine hundred twenty-three".