21051450254 has 8 divisors (see below), whose sum is σ = 33239132040. Its totient is φ = 9971739576.

The previous prime is 21051450253. The next prime is 21051450269. The reversal of 21051450254 is 45205415012.

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

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21051450253) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 276992729 + ... + 276992804.

It is an arithmetic number, because the mean of its divisors is an integer number (4154891505).

Almost surely, 2^21051450254 is an apocalyptic number.

21051450254 is a deficient number, since it is larger than the sum of its proper divisors (12187681786).

21051450254 is a wasteful number, since it uses less digits than its factorization.

21051450254 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 553985554.

The product of its (nonzero) digits is 8000, while the sum is 29.

Adding to 21051450254 its reverse (45205415012), we get a palindrome (66256865266).

The spelling of 21051450254 in words is "twenty-one billion, fifty-one million, four hundred fifty thousand, two hundred fifty-four".