21001023002 has 8 divisors (see below), whose sum is σ = 31512646836. Its totient is φ = 10496807392.

The previous prime is 21001022989. The next prime is 21001023023. The reversal of 21001023002 is 20032010012.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 17705229721 + 3295793281 = 133061^2 + 57409^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1844963 + ... + 1856310.

Almost surely, 2^21001023002 is an apocalyptic number.

21001023002 is a deficient number, since it is larger than the sum of its proper divisors (10511623834).

21001023002 is a wasteful number, since it uses less digits than its factorization.

21001023002 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3704112.

The product of its (nonzero) digits is 24, while the sum is 11.

Adding to 21001023002 its reverse (20032010012), we get a palindrome (41033033014).

The spelling of 21001023002 in words is "twenty-one billion, one million, twenty-three thousand, two".