20278090 has 32 divisors (see below), whose sum is σ = 42061824. Its totient is φ = 6894720.

The previous prime is 20278079. The next prime is 20278091. The reversal of 20278090 is 9087202.

It is a super-2 number, since 2×20278090² = 822401868096200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20278091) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7750 + ... + 10030.

It is an arithmetic number, because the mean of its divisors is an integer number (1314432).

Almost surely, 2^20278090 is an apocalyptic number.

20278090 is an abundant number, since it is smaller than the sum of its proper divisors (21783734).

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

20278090 is a wasteful number, since it uses less digits than its factorization.

20278090 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2422.

The product of its (nonzero) digits is 2016, while the sum is 28.

The square root of 20278090 is about 4503.1200294907. The cubic root of 20278090 is about 272.6940625891.

The spelling of 20278090 in words is "twenty million, two hundred seventy-eight thousand, ninety".