21896507 has 2 divisors, whose sum is σ = 21896508. Its totient is φ = 21896506.

The previous prime is 21896491. The next prime is 21896543. The reversal of 21896507 is 70569812.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21896507 - 2⁴ = 21896491 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is not a weakly prime, because it can be changed into another prime (21896597) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10948253 + 10948254.

It is an arithmetic number, because the mean of its divisors is an integer number (10948254).

Almost surely, 2^21896507 is an apocalyptic number.

21896507 is a deficient number, since it is larger than the sum of its proper divisors (1).

21896507 is an equidigital number, since it uses as much as digits as its factorization.

21896507 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 30240, while the sum is 38.

The square root of 21896507 is about 4679.3703636280. The cubic root of 21896507 is about 279.7638612819.

The spelling of 21896507 in words is "twenty-one million, eight hundred ninety-six thousand, five hundred seven".