21026210 has 16 divisors (see below), whose sum is σ = 37937592. Its totient is φ = 8390400.

The previous prime is 21026197. The next prime is 21026231. The reversal of 21026210 is 1262012.

It can be written as a sum of positive squares in 4 ways, for example, as 13535041 + 7491169 = 3679^2 + 2737^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2330 + ... + 6890.

Almost surely, 2^21026210 is an apocalyptic number.

21026210 is a deficient number, since it is larger than the sum of its proper divisors (16911382).

21026210 is a wasteful number, since it uses less digits than its factorization.

21026210 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5029.

The product of its (nonzero) digits is 48, while the sum is 14.

The square root of 21026210 is about 4585.4345486551. The cubic root of 21026210 is about 276.0071499233.

Adding to 21026210 its reverse (1262012), we get a palindrome (22288222).

The spelling of 21026210 in words is "twenty-one million, twenty-six thousand, two hundred ten".