691199999997 has 32 divisors (see below), whose sum is σ = 1019422604928. Its totient is φ = 413814686976.

The previous prime is 691199999981. The next prime is 691200000019. The reversal of 691199999997 is 799999991196.

It is not a de Polignac number, because 691199999997 - 2⁴ = 691199999981 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (691199999197) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 18701578 + ... + 18738500.

It is an arithmetic number, because the mean of its divisors is an integer number (31856956404).

Almost surely, 2^691199999997 is an apocalyptic number.

It is an amenable number.

691199999997 is a deficient number, since it is larger than the sum of its proper divisors (328222604931).

691199999997 is a wasteful number, since it uses less digits than its factorization.

691199999997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49949.

The product of its digits is 1807962282, while the sum is 87.

The spelling of 691199999997 in words is "six hundred ninety-one billion, one hundred ninety-nine million, nine hundred ninety-nine thousand, nine hundred ninety-seven".