21021402 has 48 divisors (see below), whose sum is σ = 45390240. Its totient is φ = 6484896.

The previous prime is 21021389. The next prime is 21021419. The reversal of 21021402 is 20412012.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 117349 + ... + 117527.

It is an arithmetic number, because the mean of its divisors is an integer number (945630).

Almost surely, 2^21021402 is an apocalyptic number.

21021402 is an abundant number, since it is smaller than the sum of its proper divisors (24368838).

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

21021402 is a wasteful number, since it uses less digits than its factorization.

21021402 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 267 (or 244 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 12.

The square root of 21021402 is about 4584.9102499395. The cubic root of 21021402 is about 275.9861104121.

Adding to 21021402 its reverse (20412012), we get a palindrome (41433414).

It can be divided in two parts, 210 and 21402, that added together give a palindrome (21612).

The spelling of 21021402 in words is "twenty-one million, twenty-one thousand, four hundred two".