1397840697 has 24 divisors (see below), whose sum is σ = 2318590560. Its totient is φ = 802586880.

The previous prime is 1397840693. The next prime is 1397840699. The reversal of 1397840697 is 7960487931.

It is a happy number.

It is not a de Polignac number, because 1397840697 - 2² = 1397840693 is a prime.

It is a super-2 number, since 2×1397840697² = 3907917228378891618, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1397840693) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 369688 + ... + 373449.

It is an arithmetic number, because the mean of its divisors is an integer number (96607940).

Almost surely, 2^1397840697 is an apocalyptic number.

It is an amenable number.

1397840697 is a deficient number, since it is larger than the sum of its proper divisors (920749863).

1397840697 is a wasteful number, since it uses less digits than its factorization.

1397840697 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 743173 (or 743170 counting only the distinct ones).

The product of its (nonzero) digits is 2286144, while the sum is 54.

The square root of 1397840697 is about 37387.7078329228. The cubic root of 1397840697 is about 1118.1135060443.

The spelling of 1397840697 in words is "one billion, three hundred ninety-seven million, eight hundred forty thousand, six hundred ninety-seven".