328401921 has 16 divisors (see below), whose sum is σ = 441653760. Its totient is φ = 217050240.

The previous prime is 328401911. The next prime is 328401929. The reversal of 328401921 is 129104823.

It is not a de Polignac number, because 328401921 - 2¹³ = 328393729 is a prime.

It is not an unprimeable number, because it can be changed into a prime (328401929) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 247941 + ... + 249261.

It is an arithmetic number, because the mean of its divisors is an integer number (27603360).

Almost surely, 2^328401921 is an apocalyptic number.

It is an amenable number.

328401921 is a deficient number, since it is larger than the sum of its proper divisors (113251839).

328401921 is a wasteful number, since it uses less digits than its factorization.

328401921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1976.

The product of its (nonzero) digits is 3456, while the sum is 30.

The square root of 328401921 is about 18121.8630664730. The cubic root of 328401921 is about 689.9250223088.

The spelling of 328401921 in words is "three hundred twenty-eight million, four hundred one thousand, nine hundred twenty-one".