21053699 has 2 divisors, whose sum is σ = 21053700. Its totient is φ = 21053698.

The previous prime is 21053663. The next prime is 21053707. The reversal of 21053699 is 99635012.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21053699 is a prime.

It is not a weakly prime, because it can be changed into another prime (21053609) 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 as a sum of consecutive naturals, namely, 10526849 + 10526850.

It is an arithmetic number, because the mean of its divisors is an integer number (10526850).

Almost surely, 2^21053699 is an apocalyptic number.

21053699 is a deficient number, since it is larger than the sum of its proper divisors (1).

21053699 is an equidigital number, since it uses as much as digits as its factorization.

21053699 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 14580, while the sum is 35.

The square root of 21053699 is about 4588.4309954493. The cubic root of 21053699 is about 276.1273785418.

The spelling of 21053699 in words is "twenty-one million, fifty-three thousand, six hundred ninety-nine".