2540211521 has 4 divisors (see below), whose sum is σ = 2540827332. Its totient is φ = 2539595712.

The previous prime is 2540211511. The next prime is 2540211533. The reversal of 2540211521 is 1251120452.

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 598487296 + 1941724225 = 24464^2 + 44065^2 .

It is a cyclic number.

It is not a de Polignac number, because 2540211521 - 2¹⁴ = 2540195137 is a prime.

It is a super-2 number, since 2×2540211521² = 12905349142842266882, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2540211511) 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, 301676 + ... + 309981.

It is an arithmetic number, because the mean of its divisors is an integer number (635206833).

Almost surely, 2^2540211521 is an apocalyptic number.

It is an amenable number.

2540211521 is a deficient number, since it is larger than the sum of its proper divisors (615811).

2540211521 is an equidigital number, since it uses as much as digits as its factorization.

2540211521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 615810.

The product of its (nonzero) digits is 800, while the sum is 23.

The square root of 2540211521 is about 50400.5111184401. The cubic root of 2540211521 is about 1364.4468628785.

Adding to 2540211521 its reverse (1251120452), we get a palindrome (3791331973).

The spelling of 2540211521 in words is "two billion, five hundred forty million, two hundred eleven thousand, five hundred twenty-one".