1642399 has 4 divisors (see below), whose sum is σ = 1791720. Its totient is φ = 1493080.

The previous prime is 1642397. The next prime is 1642423. The reversal of 1642399 is 9932461.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1642399 - 2¹ = 1642397 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 (1642397) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 74644 + ... + 74665.

It is an arithmetic number, because the mean of its divisors is an integer number (447930).

2^1642399 is an apocalyptic number.

1642399 is a deficient number, since it is larger than the sum of its proper divisors (149321).

1642399 is a wasteful number, since it uses less digits than its factorization.

1642399 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 149320.

The product of its digits is 11664, while the sum is 34.

The square root of 1642399 is about 1281.5611573390. The cubic root of 1642399 is about 117.9848443621.

The spelling of 1642399 in words is "one million, six hundred forty-two thousand, three hundred ninety-nine".