129187422 has 144 divisors (see below), whose sum is σ = 369729360. Its totient is φ = 32223744.

The previous prime is 129187397. The next prime is 129187427. The reversal of 129187422 is 224781921.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129187427) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 217558 + ... + 218150.

It is an arithmetic number, because the mean of its divisors is an integer number (2567565).

Almost surely, 2^129187422 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 129187422, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (184864680).

129187422 is an abundant number, since it is smaller than the sum of its proper divisors (240541938).

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

129187422 is a wasteful number, since it uses less digits than its factorization.

129187422 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 647 (or 637 counting only the distinct ones).

The product of its digits is 16128, while the sum is 36.

The square root of 129187422 is about 11366.0644904030. The cubic root of 129187422 is about 505.5220194278.

The spelling of 129187422 in words is "one hundred twenty-nine million, one hundred eighty-seven thousand, four hundred twenty-two".