2001036735781 has 4 divisors (see below), whose sum is σ = 2023520294700. Its totient is φ = 1978553176864.

The previous prime is 2001036735757. The next prime is 2001036735791. The reversal of 2001036735781 is 1875376301002.

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 940618721025 + 1060418014756 = 969855^2 + 1029766^2 .

It is a cyclic number.

It is not a de Polignac number, because 2001036735781 - 2⁵ = 2001036735749 is a prime.

It is a super-2 number, since 2×2001036735781² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2001036735791) 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, 11241779326 + ... + 11241779503.

It is an arithmetic number, because the mean of its divisors is an integer number (505880073675).

Almost surely, 2^{2001036735781} is an apocalyptic number.

It is an amenable number.

2001036735781 is a deficient number, since it is larger than the sum of its proper divisors (22483558919).

2001036735781 is an equidigital number, since it uses as much as digits as its factorization.

2001036735781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22483558918.

The product of its (nonzero) digits is 211680, while the sum is 43.

The spelling of 2001036735781 in words is "two trillion, one billion, thirty-six million, seven hundred thirty-five thousand, seven hundred eighty-one".