21021231002 has 4 divisors (see below), whose sum is σ = 31531846506. Its totient is φ = 10510615500.

The previous prime is 21021230981. The next prime is 21021231013. The reversal of 21021231002 is 20013212012.

It is a happy number.

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., 17638761721 + 3382469281 = 132811^2 + 58159^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5255307749 + ... + 5255307752.

Almost surely, 2^21021231002 is an apocalyptic number.

21021231002 is a deficient number, since it is larger than the sum of its proper divisors (10510615504).

21021231002 is a wasteful number, since it uses less digits than its factorization.

21021231002 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10510615503.

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

Adding to 21021231002 its reverse (20013212012), we get a palindrome (41034443014).

The spelling of 21021231002 in words is "twenty-one billion, twenty-one million, two hundred thirty-one thousand, two".