2097278561 has 4 divisors (see below), whose sum is σ = 2396889792. Its totient is φ = 1797667332.

The previous prime is 2097278549. The next prime is 2097278587. The reversal of 2097278561 is 1658727902.

It is a happy number.

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 2097278561 - 2⁶ = 2097278497 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (2097278591) 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, 149805605 + ... + 149805618.

It is an arithmetic number, because the mean of its divisors is an integer number (599222448).

Almost surely, 2^2097278561 is an apocalyptic number.

It is an amenable number.

2097278561 is a deficient number, since it is larger than the sum of its proper divisors (299611231).

2097278561 is an equidigital number, since it uses as much as digits as its factorization.

2097278561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 299611230.

The product of its (nonzero) digits is 423360, while the sum is 47.

The square root of 2097278561 is about 45796.0539893996. The cubic root of 2097278561 is about 1280.0257483834.

The spelling of 2097278561 in words is "two billion, ninety-seven million, two hundred seventy-eight thousand, five hundred sixty-one".