691201040 has 20 divisors (see below), whose sum is σ = 1607042604. Its totient is φ = 276480384.

The previous prime is 691201013. The next prime is 691201067. The reversal of 691201040 is 40102196.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (691201013) and next prime (691201067).

It can be written as a sum of positive squares in 2 ways, for example, as 307511296 + 383689744 = 17536^2 + 19588^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a junction number, because it is equal to n+sod(n) for n = 691200997 and 691201015.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4319927 + ... + 4320086.

Almost surely, 2^691201040 is an apocalyptic number.

It is an amenable number.

691201040 is an abundant number, since it is smaller than the sum of its proper divisors (915841564).

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

691201040 is a wasteful number, since it uses less digits than its factorization.

691201040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8640026 (or 8640020 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 23.

The square root of 691201040 is about 26290.7025391107. The cubic root of 691201040 is about 884.1680031217.

The spelling of 691201040 in words is "six hundred ninety-one million, two hundred one thousand, forty".