691289049 has 32 divisors (see below), whose sum is σ = 1034740224. Its totient is φ = 406961280.

The previous prime is 691288999. The next prime is 691289059. The reversal of 691289049 is 940982196.

It is not a de Polignac number, because 691289049 - 2⁹ = 691288537 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 691288989 and 691289007.

It is not an unprimeable number, because it can be changed into a prime (691289059) 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, 159262 + ... + 163544.

It is an arithmetic number, because the mean of its divisors is an integer number (32335632).

Almost surely, 2^691289049 is an apocalyptic number.

It is an amenable number.

691289049 is a deficient number, since it is larger than the sum of its proper divisors (343451175).

691289049 is a wasteful number, since it uses less digits than its factorization.

691289049 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4437.

The product of its (nonzero) digits is 279936, while the sum is 48.

The square root of 691289049 is about 26292.3762524425. The cubic root of 691289049 is about 884.2055278720.

The spelling of 691289049 in words is "six hundred ninety-one million, two hundred eighty-nine thousand, forty-nine".