21213702 has 24 divisors (see below), whose sum is σ = 46093320. Its totient is φ = 7051200.

The previous prime is 21213697. The next prime is 21213707. The reversal of 21213702 is 20731212.

It is an interprime number because it is at equal distance from previous prime (21213697) and next prime (21213707).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21213707) 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, 5749 + ... + 8687.

It is an arithmetic number, because the mean of its divisors is an integer number (1920555).

Almost surely, 2^21213702 is an apocalyptic number.

21213702 is an abundant number, since it is smaller than the sum of its proper divisors (24879618).

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

21213702 is a wasteful number, since it uses less digits than its factorization.

21213702 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3348 (or 3345 counting only the distinct ones).

The product of its (nonzero) digits is 168, while the sum is 18.

The square root of 21213702 is about 4605.8334750618. The cubic root of 21213702 is about 276.8251143167.

Adding to 21213702 its reverse (20731212), we get a palindrome (41944914).

The spelling of 21213702 in words is "twenty-one million, two hundred thirteen thousand, seven hundred two".