21265652434 has 16 divisors (see below), whose sum is σ = 34358307480. Its totient is φ = 9813173760.

The previous prime is 21265652423. The next prime is 21265652437. The reversal of 21265652434 is 43425656212.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 9699295225 + 11566357209 = 98485^2 + 107547^2 .

It is not an unprimeable number, because it can be changed into a prime (21265652437) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 82914 + ... + 222274.

Almost surely, 2^21265652434 is an apocalyptic number.

21265652434 is a deficient number, since it is larger than the sum of its proper divisors (13092655046).

21265652434 is a wasteful number, since it uses less digits than its factorization.

21265652434 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 145245.

The product of its digits is 345600, while the sum is 40.

The spelling of 21265652434 in words is "twenty-one billion, two hundred sixty-five million, six hundred fifty-two thousand, four hundred thirty-four".