21202145452 has 24 divisors (see below), whose sum is σ = 37737627200. Its totient is φ = 10421139456.

The previous prime is 21202145431. The next prime is 21202145479. The reversal of 21202145452 is 25454120212.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 21202145452.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 74133 + ... + 218860.

Almost surely, 2^21202145452 is an apocalyptic number.

It is an amenable number.

21202145452 is a deficient number, since it is larger than the sum of its proper divisors (16535481748).

21202145452 is a wasteful number, since it uses less digits than its factorization.

21202145452 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 293305 (or 293303 counting only the distinct ones).

The product of its (nonzero) digits is 6400, while the sum is 28.

Adding to 21202145452 its reverse (25454120212), we get a palindrome (46656265664).

The spelling of 21202145452 in words is "twenty-one billion, two hundred two million, one hundred forty-five thousand, four hundred fifty-two".