21154435452 has 36 divisors (see below), whose sum is σ = 56619225936. Its totient is φ = 6636685440.

The previous prime is 21154435447. The next prime is 21154435453. The reversal of 21154435452 is 25453445112.

21154435452 is a `hidden beast` number, since 2 + 11 + 544 + 3 + 54 + 52 = 666.

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21154435453) 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 11 ways as a sum of consecutive naturals, for example, 17282424 + ... + 17283647.

It is an arithmetic number, because the mean of its divisors is an integer number (1572756276).

Almost surely, 2^21154435452 is an apocalyptic number.

It is an amenable number.

21154435452 is an abundant number, since it is smaller than the sum of its proper divisors (35464790484).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21154435452 is a wasteful number, since it uses less digits than its factorization.

21154435452 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34566098 (or 34566093 counting only the distinct ones).

The product of its digits is 96000, while the sum is 36.

The spelling of 21154435452 in words is "twenty-one billion, one hundred fifty-four million, four hundred thirty-five thousand, four hundred fifty-two".