21932019 has 8 divisors (see below), whose sum is σ = 32491920. Its totient is φ = 14621328.

The previous prime is 21931997. The next prime is 21932039. The reversal of 21932019 is 91023912.

It is not a de Polignac number, because 21932019 - 2⁷ = 21931891 is a prime.

It is a super-2 number, since 2×21932019² = 962026914832722, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 812297 = 21932019 / (2 + 1 + 9 + 3 + 2 + 0 + 1 + 9).

It is a junction number, because it is equal to n+sod(n) for n = 21931983 and 21932001.

It is not an unprimeable number, because it can be changed into a prime (21932039) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 406122 + ... + 406175.

It is an arithmetic number, because the mean of its divisors is an integer number (4061490).

Almost surely, 2^21932019 is an apocalyptic number.

21932019 is a deficient number, since it is larger than the sum of its proper divisors (10559901).

21932019 is an equidigital number, since it uses as much as digits as its factorization.

21932019 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 812306 (or 812300 counting only the distinct ones).

The product of its (nonzero) digits is 972, while the sum is 27.

The square root of 21932019 is about 4683.1633539735. The cubic root of 21932019 is about 279.9150209805.

The spelling of 21932019 in words is "twenty-one million, nine hundred thirty-two thousand, nineteen".