67128278931 has 64 divisors (see below), whose sum is σ = 117728640000. Its totient is φ = 36988068096.

The previous prime is 67128278927. The next prime is 67128278939. The reversal of 67128278931 is 13987282176.

It is a happy number.

It is not a de Polignac number, because 67128278931 - 2² = 67128278927 is a prime.

It is a super-2 number, since 2×67128278931² (a number of 22 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (67128278939) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 4426560 + ... + 4441698.

It is an arithmetic number, because the mean of its divisors is an integer number (1839510000).

Almost surely, 2^67128278931 is an apocalyptic number.

67128278931 is a deficient number, since it is larger than the sum of its proper divisors (50600361069).

67128278931 is a wasteful number, since it uses less digits than its factorization.

67128278931 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15993 (or 15987 counting only the distinct ones).

The product of its digits is 2032128, while the sum is 54.

The spelling of 67128278931 in words is "sixty-seven billion, one hundred twenty-eight million, two hundred seventy-eight thousand, nine hundred thirty-one".