1997955 has 24 divisors (see below), whose sum is σ = 3584880. Its totient is φ = 1028160.

The previous prime is 1997939. The next prime is 1997969. The reversal of 1997955 is 5597991.

It is not a de Polignac number, because 1997955 - 2⁴ = 1997939 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 1997955.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 540 + ... + 2070.

It is an arithmetic number, because the mean of its divisors is an integer number (149370).

2^1997955 is an apocalyptic number.

1997955 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1997955 is a deficient number, since it is larger than the sum of its proper divisors (1586925).

1997955 is a wasteful number, since it uses less digits than its factorization.

1997955 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1571 (or 1568 counting only the distinct ones).

The product of its digits is 127575, while the sum is 45.

The square root of 1997955 is about 1413.4903607736. The cubic root of 1997955 is about 125.9491480359.

The spelling of 1997955 in words is "one million, nine hundred ninety-seven thousand, nine hundred fifty-five".