21175719746 has 8 divisors (see below), whose sum is σ = 32362892604. Its totient is φ = 10388088880.

The previous prime is 21175719731. The next prime is 21175719749. The reversal of 21175719746 is 64791757112.

It can be written as a sum of positive squares in 2 ways, for example, as 20179623025 + 996096721 = 142055^2 + 31561^2 .

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

It is a super-2 number, since 2×21175719746² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21175719694 and 21175719703.

It is not an unprimeable number, because it can be changed into a prime (21175719749) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 99885365 + ... + 99885576.

Almost surely, 2^21175719746 is an apocalyptic number.

21175719746 is a deficient number, since it is larger than the sum of its proper divisors (11187172858).

21175719746 is a wasteful number, since it uses less digits than its factorization.

21175719746 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 199770996.

The product of its digits is 740880, while the sum is 50.

The spelling of 21175719746 in words is "twenty-one billion, one hundred seventy-five million, seven hundred nineteen thousand, seven hundred forty-six".