691366397 has 8 divisors (see below), whose sum is σ = 707961600. Its totient is φ = 674902800.

The previous prime is 691366391. The next prime is 691366411. The reversal of 691366397 is 793663196.

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 691366397 - 2¹⁰ = 691365373 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (691366391) 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, 22229 + ... + 43322.

It is an arithmetic number, because the mean of its divisors is an integer number (88495200).

Almost surely, 2^691366397 is an apocalyptic number.

It is an amenable number.

691366397 is a deficient number, since it is larger than the sum of its proper divisors (16595203).

691366397 is a wasteful number, since it uses less digits than its factorization.

691366397 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65803.

The product of its digits is 1102248, while the sum is 50.

The square root of 691366397 is about 26293.8471319813. The cubic root of 691366397 is about 884.2385044196.

The spelling of 691366397 in words is "six hundred ninety-one million, three hundred sixty-six thousand, three hundred ninety-seven".