2665216261 has 8 divisors (see below), whose sum is σ = 2757696480. Its totient is φ = 2572774512.

The previous prime is 2665216243. The next prime is 2665216273. The reversal of 2665216261 is 1626125662.

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 2665216261 - 2¹⁹ = 2664691973 is a prime.

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 2665216261.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2665216201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 257166 + ... + 267328.

It is an arithmetic number, because the mean of its divisors is an integer number (344712060).

Almost surely, 2^2665216261 is an apocalyptic number.

It is an amenable number.

2665216261 is a deficient number, since it is larger than the sum of its proper divisors (92480219).

2665216261 is a wasteful number, since it uses less digits than its factorization.

2665216261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19235.

The product of its digits is 51840, while the sum is 37.

The square root of 2665216261 is about 51625.7325468608. The cubic root of 2665216261 is about 1386.4710893257.

The spelling of 2665216261 in words is "two billion, six hundred sixty-five million, two hundred sixteen thousand, two hundred sixty-one".