2520813681 has 6 divisors (see below), whose sum is σ = 3641175330. Its totient is φ = 1680542448.

The previous prime is 2520813671. The next prime is 2520813683. The reversal of 2520813681 is 1863180252.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 1580778081 + 940035600 = 39759^2 + 30660^2 .

It is not a de Polignac number, because 2520813681 - 2¹¹ = 2520811633 is a prime.

It is a super-2 number, since 2×2520813681² = 12709003228633539522, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (2520813683) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 140045196 + ... + 140045213.

It is an arithmetic number, because the mean of its divisors is an integer number (606862555).

Almost surely, 2^2520813681 is an apocalyptic number.

It is an amenable number.

2520813681 is a deficient number, since it is larger than the sum of its proper divisors (1120361649).

2520813681 is a wasteful number, since it uses less digits than its factorization.

2520813681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 280090415 (or 280090412 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 36.

The square root of 2520813681 is about 50207.7053946902. The cubic root of 2520813681 is about 1360.9648719924.

The spelling of 2520813681 in words is "two billion, five hundred twenty million, eight hundred thirteen thousand, six hundred eighty-one".