21135153492 has 18 divisors (see below), whose sum is σ = 53424971418. Its totient is φ = 7045051152.

The previous prime is 21135153467. The next prime is 21135153511. The reversal of 21135153492 is 29435153112.

It is a happy number.

21135153492 is a `hidden beast` number, since 2 + 1 + 1 + 35 + 1 + 534 + 92 = 666.

It can be written as a sum of positive squares in only one way, i.e., 15716132496 + 5419020996 = 125364^2 + 73614^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a Harshad number since it is a multiple of its sum of digits (36), and also a Moran number because the ratio is a prime number: 587087597 = 21135153492 / (2 + 1 + 1 + 3 + 5 + 1 + 5 + 3 + 4 + 9 + 2).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 293543763 + ... + 293543834.

Almost surely, 2^21135153492 is an apocalyptic number.

It is an amenable number.

21135153492 is an abundant number, since it is smaller than the sum of its proper divisors (32289817926).

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

21135153492 is a wasteful number, since it uses less digits than its factorization.

21135153492 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 587087607 (or 587087602 counting only the distinct ones).

The product of its digits is 32400, while the sum is 36.

The spelling of 21135153492 in words is "twenty-one billion, one hundred thirty-five million, one hundred fifty-three thousand, four hundred ninety-two".