21361356757 has 8 divisors (see below), whose sum is σ = 23096193120. Its totient is φ = 19639614000.

The previous prime is 21361356721. The next prime is 21361356763. The reversal of 21361356757 is 75765316312.

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 21361356757 - 2¹⁵ = 21361323989 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21361356707) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3270007 + ... + 3276532.

It is an arithmetic number, because the mean of its divisors is an integer number (2887024140).

Almost surely, 2^21361356757 is an apocalyptic number.

It is an amenable number.

21361356757 is a deficient number, since it is larger than the sum of its proper divisors (1734836363).

21361356757 is a wasteful number, since it uses less digits than its factorization.

21361356757 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6546803.

The product of its digits is 793800, while the sum is 46.

The spelling of 21361356757 in words is "twenty-one billion, three hundred sixty-one million, three hundred fifty-six thousand, seven hundred fifty-seven".