21284037557 has 8 divisors (see below), whose sum is σ = 22406772960. Its totient is φ = 20161554480.

The previous prime is 21284037529. The next prime is 21284037571. The reversal of 21284037557 is 75573048212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21284037557 - 2¹⁴ = 21284021173 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21284037157) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 124382 + ... + 240912.

It is an arithmetic number, because the mean of its divisors is an integer number (2800846620).

Almost surely, 2^21284037557 is an apocalyptic number.

It is an amenable number.

21284037557 is a deficient number, since it is larger than the sum of its proper divisors (1122735403).

21284037557 is a wasteful number, since it uses less digits than its factorization.

21284037557 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 126163.

The product of its (nonzero) digits is 470400, while the sum is 44.

The spelling of 21284037557 in words is "twenty-one billion, two hundred eighty-four million, thirty-seven thousand, five hundred fifty-seven".