31280728583081 has 4 divisors (see below), whose sum is σ = 31392047902164. Its totient is φ = 31169409264000.

The previous prime is 31280728583077. The next prime is 31280728583129. The reversal of 31280728583081 is 18038582708213.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 22982244240400 + 8298484342681 = 4793980^2 + 2880709^2 .

It is a cyclic number.

It is not a de Polignac number, because 31280728583081 - 2² = 31280728583077 is a prime.

It is a super-2 number, since 2×31280728583081² (a number of 28 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31280728583011) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 55659659120 + ... + 55659659681.

It is an arithmetic number, because the mean of its divisors is an integer number (7848011975541).

Almost surely, 2^{31280728583081} is an apocalyptic number.

It is an amenable number.

31280728583081 is a deficient number, since it is larger than the sum of its proper divisors (111319319083).

31280728583081 is a wasteful number, since it uses less digits than its factorization.

31280728583081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 111319319082.

The product of its (nonzero) digits is 5160960, while the sum is 56.

The spelling of 31280728583081 in words is "thirty-one trillion, two hundred eighty billion, seven hundred twenty-eight million, five hundred eighty-three thousand, eighty-one".