21069619 has 2 divisors, whose sum is σ = 21069620. Its totient is φ = 21069618.

The previous prime is 21069589. The next prime is 21069637. The reversal of 21069619 is 91696012.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21069619 - 2⁹ = 21069107 is a prime.

It is a super-2 number, since 2×21069619² = 887857689610322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21069649) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10534809 + 10534810.

It is an arithmetic number, because the mean of its divisors is an integer number (10534810).

Almost surely, 2^21069619 is an apocalyptic number.

21069619 is a deficient number, since it is larger than the sum of its proper divisors (1).

21069619 is an equidigital number, since it uses as much as digits as its factorization.

21069619 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5832, while the sum is 34.

The square root of 21069619 is about 4590.1654654271. The cubic root of 21069619 is about 276.1969599855.

The spelling of 21069619 in words is "twenty-one million, sixty-nine thousand, six hundred nineteen".