21113407 has 4 divisors (see below), whose sum is σ = 24129616. Its totient is φ = 18097200.

The previous prime is 21113399. The next prime is 21113423. The reversal of 21113407 is 70431112.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21113407 - 2³ = 21113399 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21113437) 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, 1508094 + ... + 1508107.

It is an arithmetic number, because the mean of its divisors is an integer number (6032404).

Almost surely, 2^21113407 is an apocalyptic number.

21113407 is a deficient number, since it is larger than the sum of its proper divisors (3016209).

21113407 is an equidigital number, since it uses as much as digits as its factorization.

21113407 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3016208.

The product of its (nonzero) digits is 168, while the sum is 19.

The square root of 21113407 is about 4594.9327525003. The cubic root of 21113407 is about 276.3881633153.

Adding to 21113407 its reverse (70431112), we get a palindrome (91544519).

The spelling of 21113407 in words is "twenty-one million, one hundred thirteen thousand, four hundred seven".