21882649 has 4 divisors (see below), whose sum is σ = 21945700. Its totient is φ = 21819600.

The previous prime is 21882613. The next prime is 21882667. The reversal of 21882649 is 94628812.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 13286025 + 8596624 = 3645^2 + 2932^2 .

It is a cyclic number.

It is not a de Polignac number, because 21882649 - 2⁹ = 21882137 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21882149) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 31002 + ... + 31699.

It is an arithmetic number, because the mean of its divisors is an integer number (5486425).

Almost surely, 2^21882649 is an apocalyptic number.

It is an amenable number.

21882649 is a deficient number, since it is larger than the sum of its proper divisors (63051).

21882649 is an equidigital number, since it uses as much as digits as its factorization.

21882649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63050.

The product of its digits is 55296, while the sum is 40.

The square root of 21882649 is about 4677.8893744936. The cubic root of 21882649 is about 279.7048292520.

The spelling of 21882649 in words is "twenty-one million, eight hundred eighty-two thousand, six hundred forty-nine".