21181701316 has 48 divisors (see below), whose sum is σ = 38088353520. Its totient is φ = 10303856640.

The previous prime is 21181701311. The next prime is 21181701337. The reversal of 21181701316 is 61310718112.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 712676416 + 20469024900 = 26696^2 + 143070^2 .

It is a super-2 number, since 2×21181701316² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21181701311) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 16033936 + ... + 16035256.

It is an arithmetic number, because the mean of its divisors is an integer number (793507365).

Almost surely, 2^21181701316 is an apocalyptic number.

It is an amenable number.

21181701316 is a deficient number, since it is larger than the sum of its proper divisors (16906652204).

21181701316 is a wasteful number, since it uses less digits than its factorization.

21181701316 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2104 (or 2102 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 31.

The spelling of 21181701316 in words is "twenty-one billion, one hundred eighty-one million, seven hundred one thousand, three hundred sixteen".