691671642 has 32 divisors (see below), whose sum is σ = 1405185408. Its totient is φ = 226930176.

The previous prime is 691671613. The next prime is 691671653. The reversal of 691671642 is 246176196.

It is a junction number, because it is equal to n+sod(n) for n = 691671594 and 691671603.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 258403 + ... + 261065.

It is an arithmetic number, because the mean of its divisors is an integer number (43912044).

Almost surely, 2^691671642 is an apocalyptic number.

691671642 is an abundant number, since it is smaller than the sum of its proper divisors (713513766).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

691671642 is a wasteful number, since it uses less digits than its factorization.

691671642 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3334.

The product of its digits is 108864, while the sum is 42.

The square root of 691671642 is about 26299.6509862774. The cubic root of 691671642 is about 884.3686185774.

The spelling of 691671642 in words is "six hundred ninety-one million, six hundred seventy-one thousand, six hundred forty-two".