21917413 has 8 divisors (see below), whose sum is σ = 26137728. Its totient is φ = 17969424.

The previous prime is 21917351. The next prime is 21917419. The reversal of 21917413 is 31471912.

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 21917413 - 2⁹ = 21916901 is a prime.

It is a super-2 number, since 2×21917413² = 960745985225138, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21917419) 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, 67906 + ... + 68227.

It is an arithmetic number, because the mean of its divisors is an integer number (3267216).

Almost surely, 2^21917413 is an apocalyptic number.

21917413 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

It is an amenable number.

21917413 is a deficient number, since it is larger than the sum of its proper divisors (4220315).

21917413 is a wasteful number, since it uses less digits than its factorization.

21917413 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 136163.

The product of its digits is 1512, while the sum is 28.

The square root of 21917413 is about 4681.6036782282. The cubic root of 21917413 is about 279.8528691296.

It can be divided in two parts, 2191 and 7413, that added together give a square (9604 = 98²).

The spelling of 21917413 in words is "twenty-one million, nine hundred seventeen thousand, four hundred thirteen".