2665061281 has 4 divisors (see below), whose sum is σ = 2666935552. Its totient is φ = 2663187012.

The previous prime is 2665061263. The next prime is 2665061291. The reversal of 2665061281 is 1821605662.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 2665061281 - 2⁷ = 2665061153 is a prime.

It is a super-2 number, since 2×2665061281² = 14205103262970721922, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2665061281.

It is not an unprimeable number, because it can be changed into a prime (2665061261) 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, 935001 + ... + 937846.

It is an arithmetic number, because the mean of its divisors is an integer number (666733888).

Almost surely, 2^2665061281 is an apocalyptic number.

It is an amenable number.

2665061281 is a deficient number, since it is larger than the sum of its proper divisors (1874271).

2665061281 is a wasteful number, since it uses less digits than its factorization.

2665061281 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1874270.

The product of its (nonzero) digits is 34560, while the sum is 37.

The square root of 2665061281 is about 51624.2315293894. The cubic root of 2665061281 is about 1386.4442147767. Note that the first 3 decimals are identical.

The spelling of 2665061281 in words is "two billion, six hundred sixty-five million, sixty-one thousand, two hundred eighty-one".