207661491 has 12 divisors (see below), whose sum is σ = 306931768. Its totient is φ = 135221184.

The previous prime is 207661471. The next prime is 207661513. The reversal of 207661491 is 194166702.

It is not a de Polignac number, because 207661491 - 2⁹ = 207660979 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (207661471) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 267910 + ... + 268683.

Almost surely, 2^207661491 is an apocalyptic number.

207661491 is a deficient number, since it is larger than the sum of its proper divisors (99270277).

207661491 is a wasteful number, since it uses less digits than its factorization.

207661491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 536642 (or 536639 counting only the distinct ones).

The product of its (nonzero) digits is 18144, while the sum is 36.

The square root of 207661491 is about 14410.4646351185. The cubic root of 207661491 is about 592.1776187800.

The spelling of 207661491 in words is "two hundred seven million, six hundred sixty-one thousand, four hundred ninety-one".