1997756859 has 16 divisors (see below), whose sum is σ = 3045312000. Its totient is φ = 1141158720.

The previous prime is 1997756837. The next prime is 1997756903. The reversal of 1997756859 is 9586577991.

It is not a de Polignac number, because 1997756859 - 2⁷ = 1997756731 is a prime.

It is a super-3 number, since 3×1997756859³ (a number of 29 digits) contains 333 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1997756859.

It is not an unprimeable number, because it can be changed into a prime (1997756459) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 47119 + ... + 78839.

It is an arithmetic number, because the mean of its divisors is an integer number (190332000).

Almost surely, 2^1997756859 is an apocalyptic number.

1997756859 is a deficient number, since it is larger than the sum of its proper divisors (1047555141).

1997756859 is a wasteful number, since it uses less digits than its factorization.

1997756859 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34730.

The product of its digits is 42865200, while the sum is 66.

The square root of 1997756859 is about 44696.2734352653. The cubic root of 1997756859 is about 1259.4498435933.

The spelling of 1997756859 in words is "one billion, nine hundred ninety-seven million, seven hundred fifty-six thousand, eight hundred fifty-nine".