2231906981765 has 8 divisors (see below), whose sum is σ = 2678361717240. Its totient is φ = 1785476692672.

The previous prime is 2231906981761. The next prime is 2231906981767. The reversal of 2231906981765 is 5671896091322.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 692625082081 + 1539281899684 = 832241^2 + 1240678^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 2231906981765 - 2² = 2231906981761 is a prime.

It is a super-3 number, since 3×2231906981765³ (a number of 38 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2231906981761) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5910134 + ... + 6276423.

It is an arithmetic number, because the mean of its divisors is an integer number (334795214655).

Almost surely, 2^{2231906981765} is an apocalyptic number.

It is an amenable number.

2231906981765 is a deficient number, since it is larger than the sum of its proper divisors (446454735475).

2231906981765 is a wasteful number, since it uses less digits than its factorization.

2231906981765 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12223191.

The product of its (nonzero) digits is 9797760, while the sum is 59.

The spelling of 2231906981765 in words is "two trillion, two hundred thirty-one billion, nine hundred six million, nine hundred eighty-one thousand, seven hundred sixty-five".