21303733653 has 6 divisors (see below), whose sum is σ = 30772059734. Its totient is φ = 14202489096.

The previous prime is 21303733621. The next prime is 21303733657. The reversal of 21303733653 is 35633730312.

It can be written as a sum of positive squares in only one way, i.e., 15113505969 + 6190227684 = 122937^2 + 78678^2 .

It is not a de Polignac number, because 21303733653 - 2⁵ = 21303733621 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21303733657) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1183540750 + ... + 1183540767.

Almost surely, 2^21303733653 is an apocalyptic number.

It is an amenable number.

21303733653 is a deficient number, since it is larger than the sum of its proper divisors (9468326081).

21303733653 is a wasteful number, since it uses less digits than its factorization.

21303733653 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2367081523 (or 2367081520 counting only the distinct ones).

The product of its (nonzero) digits is 102060, while the sum is 36.

The spelling of 21303733653 in words is "twenty-one billion, three hundred three million, seven hundred thirty-three thousand, six hundred fifty-three".