1255020399 has 24 divisors (see below), whose sum is σ = 1940603392. Its totient is φ = 809685720.

The previous prime is 1255020313. The next prime is 1255020401. The reversal of 1255020399 is 9930205521.

It is a happy number.

1255020399 is a `hidden beast` number, since 12 + 550 + 2 + 0 + 3 + 99 = 666.

It is not a de Polignac number, because 1255020399 - 2¹² = 1255016303 is a prime.

It is a super-2 number, since 2×1255020399² = 3150152403812238402, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1255020799) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 75769 + ... + 90834.

Almost surely, 2^1255020399 is an apocalyptic number.

1255020399 is a deficient number, since it is larger than the sum of its proper divisors (685582993).

1255020399 is an equidigital number, since it uses as much as digits as its factorization.

1255020399 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 166649 (or 166637 counting only the distinct ones).

The product of its (nonzero) digits is 24300, while the sum is 36.

The square root of 1255020399 is about 35426.2670768457. The cubic root of 1255020399 is about 1078.6575681699.

The spelling of 1255020399 in words is "one billion, two hundred fifty-five million, twenty thousand, three hundred ninety-nine".