997285978627 has 8 divisors (see below), whose sum is σ = 1005221060096. Its totient is φ = 989352185472.

The previous prime is 997285978621. The next prime is 997285978631. The reversal of 997285978627 is 726879582799.

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

It is a 7-Lehmer number, since φ(997285978627) divides (997285978627-1)⁷.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-997285978627 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (997285978621) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1263193 + ... + 1894789.

It is an arithmetic number, because the mean of its divisors is an integer number (125652632512).

Almost surely, 2^997285978627 is an apocalyptic number.

997285978627 is the 631597-th heptagonal number.

997285978627 is a deficient number, since it is larger than the sum of its proper divisors (7935081469).

997285978627 is a wasteful number, since it uses less digits than its factorization.

997285978627 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 644157.

The product of its digits is 1920360960, while the sum is 79.

The spelling of 997285978627 in words is "nine hundred ninety-seven billion, two hundred eighty-five million, nine hundred seventy-eight thousand, six hundred twenty-seven".