19905969 has 4 divisors (see below), whose sum is σ = 26541296. Its totient is φ = 13270644.

The previous prime is 19905961. The next prime is 19905979. The reversal of 19905969 is 96950991.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 19905969 - 2³ = 19905961 is a prime.

It is a super-2 number, since 2×19905969² = 792495203657922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19905961) 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, 3317659 + ... + 3317664.

It is an arithmetic number, because the mean of its divisors is an integer number (6635324).

Almost surely, 2^19905969 is an apocalyptic number.

It is an amenable number.

19905969 is a deficient number, since it is larger than the sum of its proper divisors (6635327).

19905969 is an equidigital number, since it uses as much as digits as its factorization.

19905969 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6635326.

The product of its (nonzero) digits is 196830, while the sum is 48.

The square root of 19905969 is about 4461.6105836346. The cubic root of 19905969 is about 271.0156942296.

The spelling of 19905969 in words is "nineteen million, nine hundred five thousand, nine hundred sixty-nine".