21043023001 has 54 divisors (see below), whose sum is σ = 29136557646. Its totient is φ = 15135120000.

The previous prime is 21043022969. The next prime is 21043023101. The reversal of 21043023001 is 10032034012.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 464833600 + 20578189401 = 21560^2 + 143451^2 .

It is not a de Polignac number, because 21043023001 - 2⁵ = 21043022969 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21043023101) by changing a digit.

It is a polite number, since it can be written in 53 ways as a sum of consecutive naturals, for example, 991501 + ... + 1012501.

Almost surely, 2^21043023001 is an apocalyptic number.

It is an amenable number.

21043023001 is a deficient number, since it is larger than the sum of its proper divisors (8093534645).

21043023001 is a wasteful number, since it uses less digits than its factorization.

21043023001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21063 (or 21032 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 16.

Adding to 21043023001 its reverse (10032034012), we get a palindrome (31075057013).

The spelling of 21043023001 in words is "twenty-one billion, forty-three million, twenty-three thousand, one".