21219404 has 6 divisors (see below), whose sum is σ = 37133964. Its totient is φ = 10609700.

The previous prime is 21219403. The next prime is 21219431. The reversal of 21219404 is 40491212.

It is a super-2 number, since 2×21219404² = 900526212230432, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21219404.

It is not an unprimeable number, because it can be changed into a prime (21219403) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2652422 + ... + 2652429.

It is an arithmetic number, because the mean of its divisors is an integer number (6188994).

Almost surely, 2^21219404 is an apocalyptic number.

It is an amenable number.

21219404 is a deficient number, since it is larger than the sum of its proper divisors (15914560).

21219404 is a wasteful number, since it uses less digits than its factorization.

21219404 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5304855 (or 5304853 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 23.

The square root of 21219404 is about 4606.4524311014. The cubic root of 21219404 is about 276.8499145676.

The spelling of 21219404 in words is "twenty-one million, two hundred nineteen thousand, four hundred four".