1971399 has 8 divisors (see below), whose sum is σ = 2742912. Its totient is φ = 1257080.

The previous prime is 1971377. The next prime is 1971401. The reversal of 1971399 is 9931791.

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 1971399 - 2⁸ = 1971143 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1971329) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 14217 + ... + 14354.

It is an arithmetic number, because the mean of its divisors is an integer number (342864).

2^1971399 is an apocalyptic number.

1971399 is a deficient number, since it is larger than the sum of its proper divisors (771513).

1971399 is a wasteful number, since it uses less digits than its factorization.

1971399 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28597.

The product of its digits is 15309, while the sum is 39.

The square root of 1971399 is about 1404.0651694277. The cubic root of 1971399 is about 125.3886357789.

It can be divided in two parts, 197 and 1399, that added together give a triangular number (1596 = T₅₆).

The spelling of 1971399 in words is "one million, nine hundred seventy-one thousand, three hundred ninety-nine".