21211002 has 24 divisors (see below), whose sum is σ = 48661236. Its totient is φ = 6654336.

The previous prime is 21210989. The next prime is 21211009. The reversal of 21211002 is 20011212.

It can be written as a sum of positive squares in 2 ways, for example, as 20875761 + 335241 = 4569^2 + 579^2 .

It is a Harshad number since it is a multiple of its sum of digits (9).

It is not an unprimeable number, because it can be changed into a prime (21211009) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 34353 + ... + 34964.

Almost surely, 2^21211002 is an apocalyptic number.

21211002 is an abundant number, since it is smaller than the sum of its proper divisors (27450234).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21211002 is a wasteful number, since it uses less digits than its factorization.

21211002 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 69342 (or 69339 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

The square root of 21211002 is about 4605.5403591761. The cubic root of 21211002 is about 276.8133693995.

Adding to 21211002 its reverse (20011212), we get a palindrome (41222214).

The spelling of 21211002 in words is "twenty-one million, two hundred eleven thousand, two".