1997357178 has 16 divisors (see below), whose sum is σ = 4204962720. Its totient is φ = 630744336.

The previous prime is 1997357147. The next prime is 1997357203. The reversal of 1997357178 is 8717537991.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (57).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8760225 + ... + 8760452.

It is an arithmetic number, because the mean of its divisors is an integer number (262810170).

Almost surely, 2^1997357178 is an apocalyptic number.

1997357178 is an abundant number, since it is smaller than the sum of its proper divisors (2207605542).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1997357178 is a wasteful number, since it uses less digits than its factorization.

1997357178 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17520701.

The product of its digits is 3333960, while the sum is 57.

The square root of 1997357178 is about 44691.8021341722. The cubic root of 1997357178 is about 1259.3658474280.

The spelling of 1997357178 in words is "one billion, nine hundred ninety-seven million, three hundred fifty-seven thousand, one hundred seventy-eight".