2540668121 has 4 divisors (see below), whose sum is σ = 2541268644. Its totient is φ = 2540067600.

The previous prime is 2540668111. The next prime is 2540668127. The reversal of 2540668121 is 1218660452.

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 2456689225 + 83978896 = 49565^2 + 9164^2 .

It is a cyclic number.

It is not a de Polignac number, because 2540668121 - 2²² = 2536473817 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2540668127) 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, 293870 + ... + 302391.

It is an arithmetic number, because the mean of its divisors is an integer number (635317161).

Almost surely, 2^2540668121 is an apocalyptic number.

It is an amenable number.

2540668121 is a deficient number, since it is larger than the sum of its proper divisors (600523).

2540668121 is an equidigital number, since it uses as much as digits as its factorization.

2540668121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 600522.

The product of its (nonzero) digits is 23040, while the sum is 35.

The square root of 2540668121 is about 50405.0406308734. The cubic root of 2540668121 is about 1364.5286105476.

The spelling of 2540668121 in words is "two billion, five hundred forty million, six hundred sixty-eight thousand, one hundred twenty-one".