2561501 has 4 divisors (see below), whose sum is σ = 2575104. Its totient is φ = 2547900.

The previous prime is 2561491. The next prime is 2561513. The reversal of 2561501 is 1051652.

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.

It is a cyclic number.

It is not a de Polignac number, because 2561501 - 2¹⁴ = 2545117 is a prime.

It is a super-2 number, since 2×2561501² = 13122574746002, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2561521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6515 + ... + 6896.

It is an arithmetic number, because the mean of its divisors is an integer number (643776).

2^2561501 is an apocalyptic number.

It is an amenable number.

2561501 is a deficient number, since it is larger than the sum of its proper divisors (13603).

2561501 is a wasteful number, since it uses less digits than its factorization.

2561501 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13602.

The product of its (nonzero) digits is 300, while the sum is 20.

The square root of 2561501 is about 1600.4689937640. The cubic root of 2561501 is about 136.8248066969.

The spelling of 2561501 in words is "two million, five hundred sixty-one thousand, five hundred one".