21479407 has 2 divisors, whose sum is σ = 21479408. Its totient is φ = 21479406.

The previous prime is 21479377. The next prime is 21479429. The reversal of 21479407 is 70497412.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21479407 is a prime.

It is a super-2 number, since 2×21479407² = 922729850143298, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21479467) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10739703 + 10739704.

It is an arithmetic number, because the mean of its divisors is an integer number (10739704).

Almost surely, 2^21479407 is an apocalyptic number.

21479407 is a deficient number, since it is larger than the sum of its proper divisors (1).

21479407 is an equidigital number, since it uses as much as digits as its factorization.

21479407 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 14112, while the sum is 34.

The square root of 21479407 is about 4634.5881154640. The cubic root of 21479407 is about 277.9760818233.

The spelling of 21479407 in words is "twenty-one million, four hundred seventy-nine thousand, four hundred seven".