21761130172 has 6 divisors (see below), whose sum is σ = 38081977808. Its totient is φ = 10880565084.

The previous prime is 21761130151. The next prime is 21761130221. The reversal of 21761130172 is 27103116712.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2720141268 + ... + 2720141275.

Almost surely, 2^21761130172 is an apocalyptic number.

It is an amenable number.

21761130172 is a deficient number, since it is larger than the sum of its proper divisors (16320847636).

21761130172 is a wasteful number, since it uses less digits than its factorization.

21761130172 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5440282547 (or 5440282545 counting only the distinct ones).

The product of its (nonzero) digits is 3528, while the sum is 31.

Adding to 21761130172 its reverse (27103116712), we get a palindrome (48864246884).

The spelling of 21761130172 in words is "twenty-one billion, seven hundred sixty-one million, one hundred thirty thousand, one hundred seventy-two".