667728481731 has 16 divisors (see below), whose sum is σ = 910187756544. Its totient is φ = 435230357184.

The previous prime is 667728481661. The next prime is 667728481741. The reversal of 667728481731 is 137184827766.

It is not a de Polignac number, because 667728481731 - 2¹⁰ = 667728480707 is a prime.

It is a super-2 number, since 2×667728481731² (a number of 24 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (667728481741) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2312290 + ... + 2584983.

It is an arithmetic number, because the mean of its divisors is an integer number (56886734784).

Almost surely, 2^667728481731 is an apocalyptic number.

667728481731 is a deficient number, since it is larger than the sum of its proper divisors (242459274813).

667728481731 is a wasteful number, since it uses less digits than its factorization.

667728481731 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4898290.

The product of its digits is 18966528, while the sum is 60.

The spelling of 667728481731 in words is "six hundred sixty-seven billion, seven hundred twenty-eight million, four hundred eighty-one thousand, seven hundred thirty-one".