1999955 has 8 divisors (see below), whose sum is σ = 2445552. Its totient is φ = 1569568.

The previous prime is 1999891. The next prime is 1999957. The reversal of 1999955 is 5599991.

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 1999955 - 2⁶ = 1999891 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1999957) 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, 3509 + ... + 4038.

It is an arithmetic number, because the mean of its divisors is an integer number (305694).

2^1999955 is an apocalyptic number.

1999955 is a deficient number, since it is larger than the sum of its proper divisors (445597).

1999955 is an equidigital number, since it uses as much as digits as its factorization.

1999955 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7605.

The product of its digits is 164025, while the sum is 47.

The square root of 1999955 is about 1414.1976523810. The cubic root of 1999955 is about 125.9911600416.

Adding to 1999955 its sum of digits (47), we get a palindrome (2000002).

It can be divided in two parts, 199 and 9955, that multiplied together give a triangular number (1981045 = T₁₉₉₀).

The spelling of 1999955 in words is "one million, nine hundred ninety-nine thousand, nine hundred fifty-five".