21177243453 has 16 divisors (see below), whose sum is σ = 28940184000. Its totient is φ = 13766593920.

The previous prime is 21177243449. The next prime is 21177243463. The reversal of 21177243453 is 35434277112.

It is not a de Polignac number, because 21177243453 - 2² = 21177243449 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21177243463) 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 15 ways as a sum of consecutive naturals, for example, 195558 + ... + 283896.

It is an arithmetic number, because the mean of its divisors is an integer number (1808761500).

Almost surely, 2^21177243453 is an apocalyptic number.

It is an amenable number.

21177243453 is a deficient number, since it is larger than the sum of its proper divisors (7762940547).

21177243453 is a wasteful number, since it uses less digits than its factorization.

21177243453 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 90332.

The product of its digits is 141120, while the sum is 39.

The spelling of 21177243453 in words is "twenty-one billion, one hundred seventy-seven million, two hundred forty-three thousand, four hundred fifty-three".