21024670757 has 4 divisors (see below), whose sum is σ = 21232835916. Its totient is φ = 20816505600.

The previous prime is 21024670747. The next prime is 21024670769. The reversal of 21024670757 is 75707642012.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 14017139236 + 7007531521 = 118394^2 + 83711^2 .

It is a cyclic number.

It is not a de Polignac number, because 21024670757 - 2¹⁰ = 21024669733 is a prime.

It is a super-3 number, since 3×21024670757³ (a number of 32 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21024670747) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 104082428 + ... + 104082629.

It is an arithmetic number, because the mean of its divisors is an integer number (5308208979).

Almost surely, 2^21024670757 is an apocalyptic number.

It is an amenable number.

21024670757 is a deficient number, since it is larger than the sum of its proper divisors (208165159).

21024670757 is a wasteful number, since it uses less digits than its factorization.

21024670757 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 208165158.

The product of its (nonzero) digits is 164640, while the sum is 41.

The spelling of 21024670757 in words is "twenty-one billion, twenty-four million, six hundred seventy thousand, seven hundred fifty-seven".