20380890 has 16 divisors (see below), whose sum is σ = 48914208. Its totient is φ = 5434896.

The previous prime is 20380889. The next prime is 20380897. The reversal of 20380890 is 9808302.

It is a Harshad number since it is a multiple of its sum of digits (30), and also a Moran number because the ratio is a prime number: 679363 = 20380890 / (2 + 0 + 3 + 8 + 0 + 8 + 9 + 0).

It is not an unprimeable number, because it can be changed into a prime (20380897) 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, 339652 + ... + 339711.

It is an arithmetic number, because the mean of its divisors is an integer number (3057138).

Almost surely, 2^20380890 is an apocalyptic number.

20380890 is an abundant number, since it is smaller than the sum of its proper divisors (28533318).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20380890 is a wasteful number, since it uses less digits than its factorization.

20380890 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 679373.

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

The square root of 20380890 is about 4514.5199080301. The cubic root of 20380890 is about 273.1540945988.

Adding to 20380890 its sum of digits (30), we get a triangular number (20380920 = T₆₃₈₄).

The spelling of 20380890 in words is "twenty million, three hundred eighty thousand, eight hundred ninety".