21880649 has 8 divisors (see below), whose sum is σ = 26477568. Its totient is φ = 17651520.

The previous prime is 21880643. The next prime is 21880657. The reversal of 21880649 is 94608812.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21880649 - 2¹² = 21876553 is a prime.

It is a super-2 number, since 2×21880649² = 957525601322402, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21880643) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 91817 + ... + 92054.

It is an arithmetic number, because the mean of its divisors is an integer number (3309696).

Almost surely, 2^21880649 is an apocalyptic number.

It is an amenable number.

21880649 is a deficient number, since it is larger than the sum of its proper divisors (4596919).

21880649 is a wasteful number, since it uses less digits than its factorization.

21880649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 183895.

The product of its (nonzero) digits is 27648, while the sum is 38.

The square root of 21880649 is about 4677.6755979867. The cubic root of 21880649 is about 279.6963076344.

The spelling of 21880649 in words is "twenty-one million, eight hundred eighty thousand, six hundred forty-nine".