21422705 has 16 divisors (see below), whose sum is σ = 27191808. Its totient is φ = 16176000.

The previous prime is 21422693. The next prime is 21422707. The reversal of 21422705 is 50722412.

It is a happy number.

It is not a de Polignac number, because 21422705 - 2⁴ = 21422689 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21422707) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4670 + ... + 8040.

It is an arithmetic number, because the mean of its divisors is an integer number (1699488).

Almost surely, 2^21422705 is an apocalyptic number.

It is an amenable number.

21422705 is a deficient number, since it is larger than the sum of its proper divisors (5769103).

21422705 is a wasteful number, since it uses less digits than its factorization.

21422705 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3448.

The product of its (nonzero) digits is 1120, while the sum is 23.

The square root of 21422705 is about 4628.4668087824. The cubic root of 21422705 is about 277.7312629966.

The spelling of 21422705 in words is "twenty-one million, four hundred twenty-two thousand, seven hundred five".