21023402102 has 4 divisors (see below), whose sum is σ = 31535103156. Its totient is φ = 10511701050.

The previous prime is 21023402077. The next prime is 21023402119. The reversal of 21023402102 is 20120432012.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5255850524 + ... + 5255850527.

It is an arithmetic number, because the mean of its divisors is an integer number (7883775789).

Almost surely, 2^21023402102 is an apocalyptic number.

21023402102 is a deficient number, since it is larger than the sum of its proper divisors (10511701054).

21023402102 is a wasteful number, since it uses less digits than its factorization.

21023402102 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10511701053.

The product of its (nonzero) digits is 192, while the sum is 17.

Adding to 21023402102 its reverse (20120432012), we get a palindrome (41143834114).

The spelling of 21023402102 in words is "twenty-one billion, twenty-three million, four hundred two thousand, one hundred two".