671407649 has 16 divisors (see below), whose sum is σ = 744714240. Its totient is φ = 600210000.

The previous prime is 671407613. The next prime is 671407691. The reversal of 671407649 is 946704176.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-671407649 is a prime.

It is a super-2 number, since 2×671407649² = 901576462271414402, which contains 22 as substring.

It is a Smith number, since the sum of its digits (44) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (671407249) 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 15 ways as a sum of consecutive naturals, for example, 234074 + ... + 236924.

It is an arithmetic number, because the mean of its divisors is an integer number (46544640).

Almost surely, 2^671407649 is an apocalyptic number.

It is an amenable number.

671407649 is a deficient number, since it is larger than the sum of its proper divisors (73306591).

671407649 is a wasteful number, since it uses less digits than its factorization.

671407649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3212.

The product of its (nonzero) digits is 254016, while the sum is 44.

The square root of 671407649 is about 25911.5350568043. The cubic root of 671407649 is about 875.6463899657.

The spelling of 671407649 in words is "six hundred seventy-one million, four hundred seven thousand, six hundred forty-nine".