21401967 has 8 divisors (see below), whose sum is σ = 29143296. Its totient is φ = 13964312.

The previous prime is 21401957. The next prime is 21401987. The reversal of 21401967 is 76910412.

It is a happy number.

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 21401967 - 2⁴ = 21401951 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21401927) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 75753 + ... + 76034.

It is an arithmetic number, because the mean of its divisors is an integer number (3642912).

Almost surely, 2^21401967 is an apocalyptic number.

21401967 is a deficient number, since it is larger than the sum of its proper divisors (7741329).

21401967 is a wasteful number, since it uses less digits than its factorization.

21401967 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 151837.

The product of its (nonzero) digits is 3024, while the sum is 30.

The square root of 21401967 is about 4626.2259996675. The cubic root of 21401967 is about 277.6416158919.

The spelling of 21401967 in words is "twenty-one million, four hundred one thousand, nine hundred sixty-seven".