2097735781 has 4 divisors (see below), whose sum is σ = 2097873100. Its totient is φ = 2097598464.

The previous prime is 2097735733. The next prime is 2097735799. The reversal of 2097735781 is 1875377902.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1875377902 = 2 ⋅937688951.

It can be written as a sum of positive squares in 2 ways, for example, as 957593025 + 1140142756 = 30945^2 + 33766^2 .

It is a cyclic number.

It is not a de Polignac number, because 2097735781 - 2²⁵ = 2064181349 is a prime.

It is a super-2 number, since 2×2097735781² = 8800990813775359922, which 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 (2097739781) 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, 42396 + ... + 77413.

It is an arithmetic number, because the mean of its divisors is an integer number (524468275).

Almost surely, 2^2097735781 is an apocalyptic number.

It is an amenable number.

2097735781 is a deficient number, since it is larger than the sum of its proper divisors (137319).

2097735781 is a wasteful number, since it uses less digits than its factorization.

2097735781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 137318.

The product of its (nonzero) digits is 740880, while the sum is 49.

The square root of 2097735781 is about 45801.0456321687. The cubic root of 2097735781 is about 1280.1187595295.

The spelling of 2097735781 in words is "two billion, ninety-seven million, seven hundred thirty-five thousand, seven hundred eighty-one".