129156031440 has 80 divisors (see below), whose sum is σ = 444870782400. Its totient is φ = 34441607808.

The previous prime is 129156031427. The next prime is 129156031471. The reversal of 129156031440 is 44130651921.

It is a happy number.

129156031440 is a `hidden beast` number, since 1 + 2 + 9 + 1 + 5 + 603 + 1 + 4 + 40 = 666.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 129156031395 and 129156031404.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 29895070 + ... + 29899389.

It is an arithmetic number, because the mean of its divisors is an integer number (5560884780).

Almost surely, 2^129156031440 is an apocalyptic number.

129156031440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

129156031440 is an abundant number, since it is smaller than the sum of its proper divisors (315714750960).

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

129156031440 is a wasteful number, since it uses less digits than its factorization.

129156031440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 59794481 (or 59794469 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 36.

The spelling of 129156031440 in words is "one hundred twenty-nine billion, one hundred fifty-six million, thirty-one thousand, four hundred forty".