21102433409 has 2 divisors, whose sum is σ = 21102433410. Its totient is φ = 21102433408.

The previous prime is 21102433399. The next prime is 21102433447. The reversal of 21102433409 is 90433420112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12279964225 + 8822469184 = 110815^2 + 93928^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21102433409 is a prime.

It is a super-2 number, since 2×21102433409² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21102439409) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10551216704 + 10551216705.

It is an arithmetic number, because the mean of its divisors is an integer number (10551216705).

Almost surely, 2^21102433409 is an apocalyptic number.

It is an amenable number.

21102433409 is a deficient number, since it is larger than the sum of its proper divisors (1).

21102433409 is an equidigital number, since it uses as much as digits as its factorization.

21102433409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5184, while the sum is 29.

The spelling of 21102433409 in words is "twenty-one billion, one hundred two million, four hundred thirty-three thousand, four hundred nine".