2581620493 has 4 divisors (see below), whose sum is σ = 2733480540. Its totient is φ = 2429760448.

The previous prime is 2581620479. The next prime is 2581620521. The reversal of 2581620493 is 3940261852.

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 2044215369 + 537405124 = 45213^2 + 23182^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2581620493 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2581620413) 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, 75929998 + ... + 75930031.

It is an arithmetic number, because the mean of its divisors is an integer number (683370135).

Almost surely, 2^2581620493 is an apocalyptic number.

It is an amenable number.

2581620493 is a deficient number, since it is larger than the sum of its proper divisors (151860047).

2581620493 is a wasteful number, since it uses less digits than its factorization.

2581620493 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 151860046.

The product of its (nonzero) digits is 103680, while the sum is 40.

The square root of 2581620493 is about 50809.6496051685. The cubic root of 2581620493 is about 1371.8210625847.

The spelling of 2581620493 in words is "two billion, five hundred eighty-one million, six hundred twenty thousand, four hundred ninety-three".