21134993 has 4 divisors (see below), whose sum is σ = 23056368. Its totient is φ = 19213620.

The previous prime is 21134989. The next prime is 21135001. The reversal of 21134993 is 39943112.

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 21134993 - 2² = 21134989 is a prime.

It is a super-2 number, since 2×21134993² = 893375858220098, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21134903) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 960671 + ... + 960692.

It is an arithmetic number, because the mean of its divisors is an integer number (5764092).

Almost surely, 2^21134993 is an apocalyptic number.

It is an amenable number.

21134993 is a deficient number, since it is larger than the sum of its proper divisors (1921375).

21134993 is a wasteful number, since it uses less digits than its factorization.

21134993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1921374.

The product of its digits is 5832, while the sum is 32.

The square root of 21134993 is about 4597.2810442695. The cubic root of 21134993 is about 276.4823228041.

The spelling of 21134993 in words is "twenty-one million, one hundred thirty-four thousand, nine hundred ninety-three".