1997876720 has 80 divisors (see below), whose sum is σ = 5620943808. Its totient is φ = 644689920.

The previous prime is 1997876701. The next prime is 1997876723. The reversal of 1997876720 is 276787991.

It is a tau number, because it is divible by the number of its divisors (80).

It is a super-2 number, since 2×1997876720² = 7983022776635916800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (56).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1997876723) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 95411 + ... + 114450.

Almost surely, 2^1997876720 is an apocalyptic number.

1997876720 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1997876720 is an abundant number, since it is smaller than the sum of its proper divisors (3623067088).

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

1997876720 is a wasteful number, since it uses less digits than its factorization.

1997876720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 209898 (or 209892 counting only the distinct ones).

The product of its (nonzero) digits is 2667168, while the sum is 56.

The square root of 1997876720 is about 44697.6142540069. The cubic root of 1997876720 is about 1259.4750311594.

The spelling of 1997876720 in words is "one billion, nine hundred ninety-seven million, eight hundred seventy-six thousand, seven hundred twenty".