997987570 has 8 divisors (see below), whose sum is σ = 1796377644. Its totient is φ = 399195024.

The previous prime is 997987561. The next prime is 997987577. The reversal of 997987570 is 75789799.

It can be written as a sum of positive squares in 2 ways, for example, as 997738569 + 249001 = 31587^2 + 499^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a junction number, because it is equal to n+sod(n) for n = 997987499 and 997987508.

It is not an unprimeable number, because it can be changed into a prime (997987577) 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 3 ways as a sum of consecutive naturals, for example, 49899369 + ... + 49899388.

Almost surely, 2^997987570 is an apocalyptic number.

997987570 is a deficient number, since it is larger than the sum of its proper divisors (798390074).

997987570 is a wasteful number, since it uses less digits than its factorization.

997987570 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 99798764.

The product of its (nonzero) digits is 10001880, while the sum is 61.

The square root of 997987570 is about 31590.9412648626. The cubic root of 997987570 is about 999.3287395102.

The spelling of 997987570 in words is "nine hundred ninety-seven million, nine hundred eighty-seven thousand, five hundred seventy".