691397007 has 24 divisors (see below), whose sum is σ = 1073431296. Its totient is φ = 394693488.

The previous prime is 691396991. The next prime is 691397009. The reversal of 691397007 is 700793196.

It is not a de Polignac number, because 691397007 - 2⁴ = 691396991 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 691397007.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (691397009) 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, 217008 + ... + 220170.

It is an arithmetic number, because the mean of its divisors is an integer number (44726304).

Almost surely, 2^691397007 is an apocalyptic number.

691397007 is a deficient number, since it is larger than the sum of its proper divisors (382034289).

691397007 is a wasteful number, since it uses less digits than its factorization.

691397007 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4667 (or 4660 counting only the distinct ones).

The product of its (nonzero) digits is 71442, while the sum is 42.

The square root of 691397007 is about 26294.4292008783. The cubic root of 691397007 is about 884.2515540082.

The spelling of 691397007 in words is "six hundred ninety-one million, three hundred ninety-seven thousand, seven".