1295257866 has 80 divisors (see below), whose sum is σ = 3088001664. Its totient is φ = 362010432.

The previous prime is 1295257849. The next prime is 1295257877. The reversal of 1295257866 is 6687525921.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 676126 + ... + 678038.

Almost surely, 2^1295257866 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1295257866, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1544000832).

1295257866 is an abundant number, since it is smaller than the sum of its proper divisors (1792743798).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1295257866 is an equidigital number, since it uses as much as digits as its factorization.

1295257866 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1993 (or 1972 counting only the distinct ones).

The product of its digits is 1814400, while the sum is 51.

The square root of 1295257866 is about 35989.6911073157. The cubic root of 1295257866 is about 1090.0642068622.

The spelling of 1295257866 in words is "one billion, two hundred ninety-five million, two hundred fifty-seven thousand, eight hundred sixty-six".