21201230451 has 24 divisors (see below), whose sum is σ = 30538002240. Its totient is φ = 13077231232.

The previous prime is 21201230447. The next prime is 21201230471. The reversal of 21201230451 is 15403210212.

It is not a de Polignac number, because 21201230451 - 2² = 21201230447 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21201230471) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 156081 + ... + 258386.

It is an arithmetic number, because the mean of its divisors is an integer number (1272416760).

Almost surely, 2^21201230451 is an apocalyptic number.

21201230451 is a deficient number, since it is larger than the sum of its proper divisors (9336771789).

21201230451 is a wasteful number, since it uses less digits than its factorization.

21201230451 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 414563 (or 414546 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 21.

Adding to 21201230451 its reverse (15403210212), we get a palindrome (36604440663).

The spelling of 21201230451 in words is "twenty-one billion, two hundred one million, two hundred thirty thousand, four hundred fifty-one".