21431002 has 4 divisors (see below), whose sum is σ = 32146506. Its totient is φ = 10715500.

The previous prime is 21430991. The next prime is 21431017. The reversal of 21431002 is 20013412.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 20967241 + 463761 = 4579^2 + 681^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5357749 + ... + 5357752.

Almost surely, 2^21431002 is an apocalyptic number.

21431002 is a deficient number, since it is larger than the sum of its proper divisors (10715504).

21431002 is a wasteful number, since it uses less digits than its factorization.

21431002 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10715503.

The product of its (nonzero) digits is 48, while the sum is 13.

The square root of 21431002 is about 4629.3630231383. The cubic root of 21431002 is about 277.7671134158.

Adding to 21431002 its reverse (20013412), we get a palindrome (41444414).

The spelling of 21431002 in words is "twenty-one million, four hundred thirty-one thousand, two".