21260407 has 4 divisors (see below), whose sum is σ = 24297616. Its totient is φ = 18223200.

The previous prime is 21260377. The next prime is 21260413. The reversal of 21260407 is 70406212.

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 21260407 - 2⁷ = 21260279 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21260417) 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, 1518594 + ... + 1518607.

It is an arithmetic number, because the mean of its divisors is an integer number (6074404).

Almost surely, 2^21260407 is an apocalyptic number.

21260407 is a deficient number, since it is larger than the sum of its proper divisors (3037209).

21260407 is an equidigital number, since it uses as much as digits as its factorization.

21260407 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3037208.

The product of its (nonzero) digits is 672, while the sum is 22.

The square root of 21260407 is about 4610.9008881129. The cubic root of 21260407 is about 277.0281221041.

Adding to 21260407 its reverse (70406212), we get a palindrome (91666619).

The spelling of 21260407 in words is "twenty-one million, two hundred sixty thousand, four hundred seven".