21951349 has 8 divisors (see below), whose sum is σ = 25128320. Its totient is φ = 18784656.

The previous prime is 21951343. The next prime is 21951353. The reversal of 21951349 is 94315912.

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 21951349 - 2⁷ = 21951221 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21951343) 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, 2752 + ... + 7174.

It is an arithmetic number, because the mean of its divisors is an integer number (3141040).

Almost surely, 2^21951349 is an apocalyptic number.

It is an amenable number.

21951349 is a deficient number, since it is larger than the sum of its proper divisors (3176971).

21951349 is an equidigital number, since it uses as much as digits as its factorization.

21951349 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5139.

The product of its digits is 9720, while the sum is 34.

The square root of 21951349 is about 4685.2266754128. The cubic root of 21951349 is about 279.9972321155.

The spelling of 21951349 in words is "twenty-one million, nine hundred fifty-one thousand, three hundred forty-nine".