21938467 has 8 divisors (see below), whose sum is σ = 22432592. Its totient is φ = 21448800.

The previous prime is 21938459. The next prime is 21938473. The reversal of 21938467 is 76483912.

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 21938467 - 2³ = 21938459 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21938417) 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 7 ways as a sum of consecutive naturals, for example, 10048 + ... + 12034.

It is an arithmetic number, because the mean of its divisors is an integer number (2804074).

Almost surely, 2^21938467 is an apocalyptic number.

21938467 is a deficient number, since it is larger than the sum of its proper divisors (494125).

21938467 is a wasteful number, since it uses less digits than its factorization.

21938467 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2229.

The product of its digits is 72576, while the sum is 40.

The square root of 21938467 is about 4683.8517269444. The cubic root of 21938467 is about 279.9424499069.

The spelling of 21938467 in words is "twenty-one million, nine hundred thirty-eight thousand, four hundred sixty-seven".