671499945 has 24 divisors (see below), whose sum is σ = 1183665600. Its totient is φ = 352061856.

The previous prime is 671499943. The next prime is 671499977. The reversal of 671499945 is 549994176.

It is a happy number.

671499945 is a `hidden beast` number, since 67 + 1 + 499 + 94 + 5 = 666.

It is not a de Polignac number, because 671499945 - 2¹ = 671499943 is a prime.

It is a super-2 number, since 2×671499945² = 901824352270006050, which contains 22 as substring.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 671499891 and 671499900.

It is not an unprimeable number, because it can be changed into a prime (671499943) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 123805 + ... + 129114.

It is an arithmetic number, because the mean of its divisors is an integer number (49319400).

Almost surely, 2^671499945 is an apocalyptic number.

It is an amenable number.

671499945 is a deficient number, since it is larger than the sum of its proper divisors (512165655).

671499945 is a wasteful number, since it uses less digits than its factorization.

671499945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 252989 (or 252986 counting only the distinct ones).

The product of its digits is 2449440, while the sum is 54.

The square root of 671499945 is about 25913.3159784694. The cubic root of 671499945 is about 875.6865121162.

The spelling of 671499945 in words is "six hundred seventy-one million, four hundred ninety-nine thousand, nine hundred forty-five".