129440209284 has 81 divisors (see below), whose sum is σ = 332986632069. Its totient is φ = 42396239520.

The previous prime is 129440209271. The next prime is 129440209291. The reversal of 129440209284 is 482902044921.

The square root of 129440209284 is 359778.

It is a perfect power (a square), and thus also a powerful number.

129440209284 is a `hidden beast` number, since 1 + 29 + 440 + 20 + 92 + 84 = 666.

It can be written as a sum of positive squares in only one way, i.e., 4209154884 + 125231054400 = 64878^2 + 353880^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 131678257 + ... + 131679239.

Almost surely, 2^129440209284 is an apocalyptic number.

129440209284 is the 359778-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 129440209284

129440209284 is an abundant number, since it is smaller than the sum of its proper divisors (203546422785).

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

129440209284 is an frugal number, since it uses more digits than its factorization.

129440209284 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2098 (or 1049 counting only the distinct ones).

The product of its (nonzero) digits is 331776, while the sum is 45.

It can be divided in two parts, 129440 and 209284, that added together give a square (338724 = 582²).

The spelling of 129440209284 in words is "one hundred twenty-nine billion, four hundred forty million, two hundred nine thousand, two hundred eighty-four".