21424500634 has 4 divisors (see below), whose sum is σ = 32136750954. Its totient is φ = 10712250316.

The previous prime is 21424500619. The next prime is 21424500637. The reversal of 21424500634 is 43600542412.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 16487330409 + 4937170225 = 128403^2 + 70265^2 .

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a junction number, because it is equal to n+sod(n) for n = 21424500596 and 21424500605.

It is not an unprimeable number, because it can be changed into a prime (21424500637) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5356125157 + ... + 5356125160.

Almost surely, 2^21424500634 is an apocalyptic number.

21424500634 is a deficient number, since it is larger than the sum of its proper divisors (10712250320).

21424500634 is a wasteful number, since it uses less digits than its factorization.

21424500634 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10712250319.

The product of its (nonzero) digits is 23040, while the sum is 31.

The spelling of 21424500634 in words is "twenty-one billion, four hundred twenty-four million, five hundred thousand, six hundred thirty-four".