255661501 has 4 divisors (see below), whose sum is σ = 257377500. Its totient is φ = 253945504.

The previous prime is 255661493. The next prime is 255661507. The reversal of 255661501 is 105166552.

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 84732025 + 170929476 = 9205^2 + 13074^2 .

It is a cyclic number.

It is not a de Polignac number, because 255661501 - 2³ = 255661493 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 (255661507) 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, 857776 + ... + 858073.

It is an arithmetic number, because the mean of its divisors is an integer number (64344375).

Almost surely, 2^255661501 is an apocalyptic number.

It is an amenable number.

255661501 is a deficient number, since it is larger than the sum of its proper divisors (1715999).

255661501 is a wasteful number, since it uses less digits than its factorization.

255661501 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1715998.

The product of its (nonzero) digits is 9000, while the sum is 31.

The square root of 255661501 is about 15989.4184071842. The cubic root of 255661501 is about 634.6804360609.

The spelling of 255661501 in words is "two hundred fifty-five million, six hundred sixty-one thousand, five hundred one".