90129809 has 8 divisors (see below), whose sum is σ = 112369728. Its totient is φ = 70230960.

The previous prime is 90129799. The next prime is 90129859. The reversal of 90129809 is 90892109.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 90129809 - 2¹² = 90125713 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (90129859) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 585182 + ... + 585335.

It is an arithmetic number, because the mean of its divisors is an integer number (14046216).

Almost surely, 2^90129809 is an apocalyptic number.

It is an amenable number.

90129809 is a deficient number, since it is larger than the sum of its proper divisors (22239919).

90129809 is a wasteful number, since it uses less digits than its factorization.

90129809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1170535.

The product of its (nonzero) digits is 11664, while the sum is 38.

The square root of 90129809 is about 9493.6720503712. The cubic root of 90129809 is about 448.3558254755.

The spelling of 90129809 in words is "ninety million, one hundred twenty-nine thousand, eight hundred nine".