21070279 has 6 divisors (see below), whose sum is σ = 21656544. Its totient is φ = 20499480.

The previous prime is 21070267. The next prime is 21070307. The reversal of 21070279 is 97207012.

It is a happy number.

It is not a de Polignac number, because 21070279 - 2¹³ = 21062087 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21070579) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 6327 + ... + 9064.

It is an arithmetic number, because the mean of its divisors is an integer number (3609424).

Almost surely, 2^21070279 is an apocalyptic number.

21070279 is a deficient number, since it is larger than the sum of its proper divisors (586265).

21070279 is an equidigital number, since it uses as much as digits as its factorization.

21070279 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15465 (or 15428 counting only the distinct ones).

The product of its (nonzero) digits is 1764, while the sum is 28.

The square root of 21070279 is about 4590.2373576973. The cubic root of 21070279 is about 276.1998438865.

The spelling of 21070279 in words is "twenty-one million, seventy thousand, two hundred seventy-nine".