2520647861 has 4 divisors (see below), whose sum is σ = 2520748512. Its totient is φ = 2520547212.

The previous prime is 2520647849. The next prime is 2520647881. The reversal of 2520647861 is 1687460252.

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, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 2520647861 - 2⁶ = 2520647797 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2520647881) 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, 19976 + ... + 73758.

It is an arithmetic number, because the mean of its divisors is an integer number (630187128).

Almost surely, 2^2520647861 is an apocalyptic number.

It is an amenable number.

2520647861 is a deficient number, since it is larger than the sum of its proper divisors (100651).

2520647861 is an equidigital number, since it uses as much as digits as its factorization.

2520647861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 100650.

The product of its (nonzero) digits is 161280, while the sum is 41.

The square root of 2520647861 is about 50206.0540273780. The cubic root of 2520647861 is about 1360.9350297573.

The spelling of 2520647861 in words is "two billion, five hundred twenty million, six hundred forty-seven thousand, eight hundred sixty-one".