618997697 has 4 divisors (see below), whose sum is σ = 619262676. Its totient is φ = 618732720.

The previous prime is 618997651. The next prime is 618997699. The reversal of 618997697 is 796799816.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 71250481 + 547747216 = 8441^2 + 23404^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-618997697 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (618997699) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 128954 + ... + 133667.

It is an arithmetic number, because the mean of its divisors is an integer number (154815669).

Almost surely, 2^618997697 is an apocalyptic number.

It is an amenable number.

618997697 is a deficient number, since it is larger than the sum of its proper divisors (264979).

618997697 is a wasteful number, since it uses less digits than its factorization.

618997697 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 264978.

The product of its digits is 10287648, while the sum is 62.

The square root of 618997697 is about 24879.6643265137. The cubic root of 618997697 is about 852.2421528224.

It can be divided in two parts, 61899 and 7697, that added together give a palindrome (69596).

The spelling of 618997697 in words is "six hundred eighteen million, nine hundred ninety-seven thousand, six hundred ninety-seven".