1287574397 has 4 divisors (see below), whose sum is σ = 1308682236. Its totient is φ = 1266466560.

The previous prime is 1287574363. The next prime is 1287574399. The reversal of 1287574397 is 7934757821.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7934757821 = 181 ⋅43838441.

It can be written as a sum of positive squares in 2 ways, for example, as 200817241 + 1086757156 = 14171^2 + 32966^2 .

It is a cyclic number.

It is not a de Polignac number, because 1287574397 - 2⁶ = 1287574333 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 (1287574399) 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, 10553828 + ... + 10553949.

It is an arithmetic number, because the mean of its divisors is an integer number (327170559).

Almost surely, 2^1287574397 is an apocalyptic number.

It is an amenable number.

1287574397 is a deficient number, since it is larger than the sum of its proper divisors (21107839).

1287574397 is an equidigital number, since it uses as much as digits as its factorization.

1287574397 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21107838.

The product of its digits is 2963520, while the sum is 53.

The square root of 1287574397 is about 35882.7869179639. The cubic root of 1287574397 is about 1087.9045106710.

The spelling of 1287574397 in words is "one billion, two hundred eighty-seven million, five hundred seventy-four thousand, three hundred ninety-seven".