19939969 has 4 divisors (see below), whose sum is σ = 22788544. Its totient is φ = 17091396.

The previous prime is 19939961. The next prime is 19939973. The reversal of 19939969 is 96993991.

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, and also an emirpimes, since its reverse is a distinct semiprime: 96993991 = 1777 ⋅54583.

It is not a de Polignac number, because 19939969 - 2³ = 19939961 is a prime.

It is a super-2 number, since 2×19939969² = 795204727441922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19939961) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1424277 + ... + 1424290.

It is an arithmetic number, because the mean of its divisors is an integer number (5697136).

Almost surely, 2^19939969 is an apocalyptic number.

It is an amenable number.

19939969 is a deficient number, since it is larger than the sum of its proper divisors (2848575).

19939969 is an equidigital number, since it uses as much as digits as its factorization.

19939969 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2848574.

The product of its digits is 1062882, while the sum is 55.

The square root of 19939969 is about 4465.4192412359. The cubic root of 19939969 is about 271.1699074766.

The spelling of 19939969 in words is "nineteen million, nine hundred thirty-nine thousand, nine hundred sixty-nine".