21167290 has 8 divisors (see below), whose sum is σ = 38101140. Its totient is φ = 8466912.

The previous prime is 21167257. The next prime is 21167297. The reversal of 21167290 is 9276112.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 17313921 + 3853369 = 4161^2 + 1963^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (21167297) 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, 1058355 + ... + 1058374.

Almost surely, 2^21167290 is an apocalyptic number.

21167290 is a deficient number, since it is larger than the sum of its proper divisors (16933850).

21167290 is a wasteful number, since it uses less digits than its factorization.

21167290 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2116736.

The product of its (nonzero) digits is 1512, while the sum is 28.

The square root of 21167290 is about 4600.7923230678. The cubic root of 21167290 is about 276.6230846981.

The spelling of 21167290 in words is "twenty-one million, one hundred sixty-seven thousand, two hundred ninety".