2565250621 has 4 divisors (see below), whose sum is σ = 2590649244. Its totient is φ = 2539852000.

The previous prime is 2565250619. The next prime is 2565250631. The reversal of 2565250621 is 1260525652.

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 1354976100 + 1210274521 = 36810^2 + 34789^2 .

It is a cyclic number.

It is not a de Polignac number, because 2565250621 - 2¹ = 2565250619 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 (2565250601) 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, 12699160 + ... + 12699361.

It is an arithmetic number, because the mean of its divisors is an integer number (647662311).

Almost surely, 2^2565250621 is an apocalyptic number.

It is an amenable number.

2565250621 is a deficient number, since it is larger than the sum of its proper divisors (25398623).

2565250621 is a wasteful number, since it uses less digits than its factorization.

2565250621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25398622.

The product of its (nonzero) digits is 36000, while the sum is 34.

The square root of 2565250621 is about 50648.3032391017. The cubic root of 2565250621 is about 1368.9153723696.

The spelling of 2565250621 in words is "two billion, five hundred sixty-five million, two hundred fifty thousand, six hundred twenty-one".