21949441 has 4 divisors (see below), whose sum is σ = 21997312. Its totient is φ = 21901572.

The previous prime is 21949409. The next prime is 21949453. The reversal of 21949441 is 14494912.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21949441 - 2⁵ = 21949409 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21949397 and 21949406.

It is not an unprimeable number, because it can be changed into a prime (21949471) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 23241 + ... + 24166.

It is an arithmetic number, because the mean of its divisors is an integer number (5499328).

Almost surely, 2^21949441 is an apocalyptic number.

It is an amenable number.

21949441 is a deficient number, since it is larger than the sum of its proper divisors (47871).

21949441 is an equidigital number, since it uses as much as digits as its factorization.

21949441 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47870.

The product of its digits is 10368, while the sum is 34.

The square root of 21949441 is about 4685.0230522378. The cubic root of 21949441 is about 279.9891194752.

The spelling of 21949441 in words is "twenty-one million, nine hundred forty-nine thousand, four hundred forty-one".