1375631399 has 8 divisors (see below), whose sum is σ = 1427379408. Its totient is φ = 1324650240.

The previous prime is 1375631371. The next prime is 1375631401. The reversal of 1375631399 is 9931365731.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1375631399 - 2²⁰ = 1374582823 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 (1375631329) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 188057 + ... + 195234.

It is an arithmetic number, because the mean of its divisors is an integer number (178422426).

Almost surely, 2^1375631399 is an apocalyptic number.

1375631399 is a deficient number, since it is larger than the sum of its proper divisors (51748009).

1375631399 is an equidigital number, since it uses as much as digits as its factorization.

1375631399 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 383425.

The product of its digits is 459270, while the sum is 47.

The square root of 1375631399 is about 37089.5052407012. The cubic root of 1375631399 is about 1112.1602275781.

The spelling of 1375631399 in words is "one billion, three hundred seventy-five million, six hundred thirty-one thousand, three hundred ninety-nine".