128121530 has 32 divisors (see below), whose sum is σ = 237945600. Its totient is φ = 49643200.

The previous prime is 128121527. The next prime is 128121557. The reversal of 128121530 is 35121821.

It is a happy number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 128121496 and 128121505.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 46121 + ... + 48819.

It is an arithmetic number, because the mean of its divisors is an integer number (7435800).

Almost surely, 2^128121530 is an apocalyptic number.

128121530 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

128121530 is a deficient number, since it is larger than the sum of its proper divisors (109824070).

128121530 is a wasteful number, since it uses less digits than its factorization.

128121530 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2854.

The product of its (nonzero) digits is 480, while the sum is 23.

The square root of 128121530 is about 11319.0781426758. The cubic root of 128121530 is about 504.1278676363.

The spelling of 128121530 in words is "one hundred twenty-eight million, one hundred twenty-one thousand, five hundred thirty".