21234503251 has 16 divisors (see below), whose sum is σ = 23584067584. Its totient is φ = 18994427424.

The previous prime is 21234503249. The next prime is 21234503273. The reversal of 21234503251 is 15230543212.

It is a cyclic number.

It is not a de Polignac number, because 21234503251 - 2¹ = 21234503249 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21234503201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 78561 + ... + 220546.

It is an arithmetic number, because the mean of its divisors is an integer number (1474004224).

Almost surely, 2^21234503251 is an apocalyptic number.

21234503251 is a deficient number, since it is larger than the sum of its proper divisors (2349564333).

21234503251 is a wasteful number, since it uses less digits than its factorization.

21234503251 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 299290.

The product of its (nonzero) digits is 7200, while the sum is 28.

The spelling of 21234503251 in words is "twenty-one billion, two hundred thirty-four million, five hundred three thousand, two hundred fifty-one".