997193581 has 8 divisors (see below), whose sum is σ = 1005715904. Its totient is φ = 988696800.

The previous prime is 997193579. The next prime is 997193627. The reversal of 997193581 is 185391799.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 997193581 - 2¹ = 997193579 is a prime.

It is a super-2 number, since 2×997193581² = 1988790075975207122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (997133581) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 76561 + ... + 88633.

It is an arithmetic number, because the mean of its divisors is an integer number (125714488).

Almost surely, 2^997193581 is an apocalyptic number.

It is an amenable number.

997193581 is a deficient number, since it is larger than the sum of its proper divisors (8522323).

997193581 is a wasteful number, since it uses less digits than its factorization.

997193581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12771.

The product of its digits is 612360, while the sum is 52.

The square root of 997193581 is about 31578.3720448031. The cubic root of 997193581 is about 999.0636505233.

The spelling of 997193581 in words is "nine hundred ninety-seven million, one hundred ninety-three thousand, five hundred eighty-one".