21243534435 has 48 divisors (see below), whose sum is σ = 37451082240. Its totient is φ = 11137988160.

The previous prime is 21243534427. The next prime is 21243534451. The reversal of 21243534435 is 53443534212.

21243534435 is a `hidden beast` number, since 212 + 4 + 3 + 5 + 3 + 4 + 435 = 666.

It is not a de Polignac number, because 21243534435 - 2³ = 21243534427 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21243534435.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 613926 + ... + 647604.

It is an arithmetic number, because the mean of its divisors is an integer number (780230880).

Almost surely, 2^21243534435 is an apocalyptic number.

21243534435 is a deficient number, since it is larger than the sum of its proper divisors (16207547805).

21243534435 is a wasteful number, since it uses less digits than its factorization.

21243534435 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33928 (or 33925 counting only the distinct ones).

The product of its digits is 172800, while the sum is 36.

The spelling of 21243534435 in words is "twenty-one billion, two hundred forty-three million, five hundred thirty-four thousand, four hundred thirty-five".