21983019 has 16 divisors (see below), whose sum is σ = 31574400. Its totient is φ = 13559616.

The previous prime is 21982973. The next prime is 21983021. The reversal of 21983019 is 91038912.

It is a de Polignac number, because none of the positive numbers 2^k-21983019 is a prime.

It is a super-2 number, since 2×21983019² = 966506248708722, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21983029) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2034 + ... + 6935.

It is an arithmetic number, because the mean of its divisors is an integer number (1973400).

Almost surely, 2^21983019 is an apocalyptic number.

21983019 is a deficient number, since it is larger than the sum of its proper divisors (9591381).

21983019 is a wasteful number, since it uses less digits than its factorization.

21983019 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9034.

The product of its (nonzero) digits is 3888, while the sum is 33.

The square root of 21983019 is about 4688.6052297032. The cubic root of 21983019 is about 280.1318214333.

It can be divided in two parts, 219 and 83019, that added together give a palindrome (83238).

The spelling of 21983019 in words is "twenty-one million, nine hundred eighty-three thousand, nineteen".