691397151 has 8 divisors (see below), whose sum is σ = 925265664. Its totient is φ = 459230040.

The previous prime is 691397143. The next prime is 691397209. The reversal of 691397151 is 151793196.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 691397151 - 2³ = 691397143 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (691397111) 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, 424401 + ... + 426026.

It is an arithmetic number, because the mean of its divisors is an integer number (115658208).

Almost surely, 2^691397151 is an apocalyptic number.

691397151 is a deficient number, since it is larger than the sum of its proper divisors (233868513).

691397151 is a wasteful number, since it uses less digits than its factorization.

691397151 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 850701.

The product of its digits is 51030, while the sum is 42.

The square root of 691397151 is about 26294.4319391007. The cubic root of 691397151 is about 884.2516153970.

The spelling of 691397151 in words is "six hundred ninety-one million, three hundred ninety-seven thousand, one hundred fifty-one".