129721319 has 16 divisors (see below), whose sum is σ = 162281280. Its totient is φ = 100949760.

The previous prime is 129721307. The next prime is 129721351. The reversal of 129721319 is 913127921.

It is a cyclic number.

It is not a de Polignac number, because 129721319 - 2⁸ = 129721063 is a prime.

It is a super-2 number, since 2×129721319² = 33655241206199522, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129721399) 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 15 ways as a sum of consecutive naturals, for example, 6134 + ... + 17235.

It is an arithmetic number, because the mean of its divisors is an integer number (10142580).

Almost surely, 2^129721319 is an apocalyptic number.

129721319 is a deficient number, since it is larger than the sum of its proper divisors (32559961).

129721319 is a wasteful number, since it uses less digits than its factorization.

129721319 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23450.

The product of its digits is 6804, while the sum is 35.

The square root of 129721319 is about 11389.5267241444. The cubic root of 129721319 is about 506.2174579702.

The spelling of 129721319 in words is "one hundred twenty-nine million, seven hundred twenty-one thousand, three hundred nineteen".