21345405254 has 16 divisors (see below), whose sum is σ = 33716723040. Its totient is φ = 10115012160.

The previous prime is 21345405227. The next prime is 21345405269. The reversal of 21345405254 is 45250454312.

It is a congruent number.

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, 2123567 + ... + 2133594.

It is an arithmetic number, because the mean of its divisors is an integer number (2107295190).

Almost surely, 2^21345405254 is an apocalyptic number.

21345405254 is a deficient number, since it is larger than the sum of its proper divisors (12371317786).

21345405254 is a wasteful number, since it uses less digits than its factorization.

21345405254 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4257295.

The product of its (nonzero) digits is 96000, while the sum is 35.

Adding to 21345405254 its reverse (45250454312), we get a palindrome (66595859566).

The spelling of 21345405254 in words is "twenty-one billion, three hundred forty-five million, four hundred five thousand, two hundred fifty-four".