20378555 has 8 divisors (see below), whose sum is σ = 24548832. Its totient is φ = 16239808.

The previous prime is 20378549. The next prime is 20378557. The reversal of 20378555 is 55587302.

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 20378555 - 2⁴ = 20378539 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20378557) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 6434 + ... + 9063.

It is an arithmetic number, because the mean of its divisors is an integer number (3068604).

Almost surely, 2^20378555 is an apocalyptic number.

20378555 is a deficient number, since it is larger than the sum of its proper divisors (4170277).

20378555 is a wasteful number, since it uses less digits than its factorization.

20378555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15765.

The product of its (nonzero) digits is 42000, while the sum is 35.

The square root of 20378555 is about 4514.2612906211. The cubic root of 20378555 is about 273.1436626178.

The spelling of 20378555 in words is "twenty million, three hundred seventy-eight thousand, five hundred fifty-five".