1397197666 has 12 divisors (see below), whose sum is σ = 2226331458. Its totient is φ = 657504512.

The previous prime is 1397197657. The next prime is 1397197673. The reversal of 1397197666 is 6667917931.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 1267716025 + 129481641 = 35605^2 + 11379^2 .

It is a super-2 number, since 2×1397197666² = 3904322635751695112, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1208071 + ... + 1209226.

Almost surely, 2^1397197666 is an apocalyptic number.

1397197666 is a deficient number, since it is larger than the sum of its proper divisors (829133792).

1397197666 is a wasteful number, since it uses less digits than its factorization.

1397197666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2417333 (or 2417316 counting only the distinct ones).

The product of its digits is 2571912, while the sum is 55.

The square root of 1397197666 is about 37379.1073462168. The cubic root of 1397197666 is about 1117.9420292030.

The spelling of 1397197666 in words is "one billion, three hundred ninety-seven million, one hundred ninety-seven thousand, six hundred sixty-six".