21100402450 has 24 divisors (see below), whose sum is σ = 39250741140. Its totient is φ = 8439302400.

The previous prime is 21100402441. The next prime is 21100402471. The reversal of 21100402450 is 5420400112.

It can be written as a sum of positive squares in 6 ways, for example, as 5709766969 + 15390635481 = 75563^2 + 124059^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 748206 + ... + 775894.

Almost surely, 2^21100402450 is an apocalyptic number.

21100402450 is a deficient number, since it is larger than the sum of its proper divisors (18150338690).

21100402450 is a wasteful number, since it uses less digits than its factorization.

21100402450 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42942 (or 42937 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 19.

Adding to 21100402450 its reverse (5420400112), we get a palindrome (26520802562).

The spelling of 21100402450 in words is "twenty-one billion, one hundred million, four hundred two thousand, four hundred fifty".