10315781721 has 24 divisors (see below), whose sum is σ = 17035746624. Its totient is φ = 5892475680.

The previous prime is 10315781687. The next prime is 10315781731. The reversal of 10315781721 is 12718751301.

10315781721 is a `hidden beast` number, since 10 + 3 + 1 + 578 + 1 + 72 + 1 = 666.

It is not a de Polignac number, because 10315781721 - 2²¹ = 10313684569 is a prime.

It is not an unprimeable number, because it can be changed into a prime (10315781731) 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 23 ways as a sum of consecutive naturals, for example, 142075 + ... + 202031.

It is an arithmetic number, because the mean of its divisors is an integer number (709822776).

Almost surely, 2^10315781721 is an apocalyptic number.

It is an amenable number.

10315781721 is a deficient number, since it is larger than the sum of its proper divisors (6719964903).

10315781721 is a wasteful number, since it uses less digits than its factorization.

10315781721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 62701 (or 62698 counting only the distinct ones).

The product of its (nonzero) digits is 11760, while the sum is 36.

The spelling of 10315781721 in words is "ten billion, three hundred fifteen million, seven hundred eighty-one thousand, seven hundred twenty-one".