21890783 has 2 divisors, whose sum is σ = 21890784. Its totient is φ = 21890782.

The previous prime is 21890777. The next prime is 21890789. The reversal of 21890783 is 38709812.

It is a balanced prime because it is at equal distance from previous prime (21890777) and next prime (21890789).

It is a cyclic number.

It is not a de Polignac number, because 21890783 - 2⁶ = 21890719 is a prime.

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

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21890789) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10945391 + 10945392.

It is an arithmetic number, because the mean of its divisors is an integer number (10945392).

Almost surely, 2^21890783 is an apocalyptic number.

21890783 is a deficient number, since it is larger than the sum of its proper divisors (1).

21890783 is an equidigital number, since it uses as much as digits as its factorization.

21890783 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 24192, while the sum is 38.

The square root of 21890783 is about 4678.7587029040. The cubic root of 21890783 is about 279.7394813218.

The spelling of 21890783 in words is "twenty-one million, eight hundred ninety thousand, seven hundred eighty-three".