21021036023 has 8 divisors (see below), whose sum is σ = 23829514800. Its totient is φ = 18382768128.

The previous prime is 21021036007. The next prime is 21021036037. The reversal of 21021036023 is 32063012012.

It is a happy number.

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

It is not a de Polignac number, because 21021036023 - 2⁴ = 21021036007 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21021035986 and 21021036004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21021036083) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 42552458 + ... + 42552951.

It is an arithmetic number, because the mean of its divisors is an integer number (2978689350).

Almost surely, 2^21021036023 is an apocalyptic number.

21021036023 is a deficient number, since it is larger than the sum of its proper divisors (2808478777).

21021036023 is a wasteful number, since it uses less digits than its factorization.

21021036023 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85105441.

The product of its (nonzero) digits is 432, while the sum is 20.

Adding to 21021036023 its reverse (32063012012), we get a palindrome (53084048035).

The spelling of 21021036023 in words is "twenty-one billion, twenty-one million, thirty-six thousand, twenty-three".