21145354479 has 40 divisors (see below), whose sum is σ = 33487859328. Its totient is φ = 13273398720.

The previous prime is 21145354471. The next prime is 21145354493. The reversal of 21145354479 is 97445354112.

21145354479 is a `hidden beast` number, since 2 + 1 + 1 + 4 + 535 + 44 + 79 = 666.

It is not a de Polignac number, because 21145354479 - 2³ = 21145354471 is a prime.

It is a super-2 number, since 2×21145354479² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21145354471) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 20892 + ... + 206705.

Almost surely, 2^21145354479 is an apocalyptic number.

21145354479 is a deficient number, since it is larger than the sum of its proper divisors (12342504849).

21145354479 is a wasteful number, since it uses less digits than its factorization.

21145354479 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 227677 (or 227668 counting only the distinct ones).

The product of its digits is 604800, while the sum is 45.

The spelling of 21145354479 in words is "twenty-one billion, one hundred forty-five million, three hundred fifty-four thousand, four hundred seventy-nine".