19902023 has 2 divisors, whose sum is σ = 19902024. Its totient is φ = 19902022.

The previous prime is 19902017. The next prime is 19902059. The reversal of 19902023 is 32020991.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 19902023 - 2²⁰ = 18853447 is a prime.

It is equal to p_1264742 and since 19902023 and 1264742 have the same sum of digits, it is a Honaker prime.

It is a junction number, because it is equal to n+sod(n) for n = 19901983 and 19902001.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19902013) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9951011 + 9951012.

It is an arithmetic number, because the mean of its divisors is an integer number (9951012).

Almost surely, 2^19902023 is an apocalyptic number.

19902023 is a deficient number, since it is larger than the sum of its proper divisors (1).

19902023 is an equidigital number, since it uses as much as digits as its factorization.

19902023 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 972, while the sum is 26.

The square root of 19902023 is about 4461.1683447276. The cubic root of 19902023 is about 270.9977850520.

The spelling of 19902023 in words is "nineteen million, nine hundred two thousand, twenty-three".