129153021 has 4 divisors (see below), whose sum is σ = 172204032. Its totient is φ = 86102012.

The previous prime is 129153007. The next prime is 129153049. The reversal of 129153021 is 120351921.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 120351921 = 3 ⋅40117307.

It is a cyclic number.

It is not a de Polignac number, because 129153021 - 2⁹ = 129152509 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 129152982 and 129153000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129153001) 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, 21525501 + ... + 21525506.

It is an arithmetic number, because the mean of its divisors is an integer number (43051008).

Almost surely, 2^129153021 is an apocalyptic number.

It is an amenable number.

129153021 is a deficient number, since it is larger than the sum of its proper divisors (43051011).

129153021 is an equidigital number, since it uses as much as digits as its factorization.

129153021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43051010.

The product of its (nonzero) digits is 540, while the sum is 24.

The square root of 129153021 is about 11364.5510690040. The cubic root of 129153021 is about 505.4771440404.

The spelling of 129153021 in words is "one hundred twenty-nine million, one hundred fifty-three thousand, twenty-one".