129678440 has 16 divisors (see below), whose sum is σ = 291776580. Its totient is φ = 51871360.

The previous prime is 129678413. The next prime is 129678443. The reversal of 129678440 is 44876921.

It can be written as a sum of positive squares in 2 ways, for example, as 127735204 + 1943236 = 11302^2 + 1394^2 .

It is not an unprimeable number, because it can be changed into a prime (129678443) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1620941 + ... + 1621020.

Almost surely, 2^129678440 is an apocalyptic number.

129678440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

129678440 is an abundant number, since it is smaller than the sum of its proper divisors (162098140).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

129678440 is a wasteful number, since it uses less digits than its factorization.

129678440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3241972 (or 3241968 counting only the distinct ones).

The product of its (nonzero) digits is 96768, while the sum is 41.

The square root of 129678440 is about 11387.6441813046. The cubic root of 129678440 is about 506.1616755935.

The spelling of 129678440 in words is "one hundred twenty-nine million, six hundred seventy-eight thousand, four hundred forty".