20281019 has 16 divisors (see below), whose sum is σ = 22879584. Its totient is φ = 17817600.

The previous prime is 20281013. The next prime is 20281039. The reversal of 20281019 is 91018202.

It is a cyclic number.

It is not a de Polignac number, because 20281019 - 2⁴ = 20281003 is a prime.

It is a super-2 number, since 2×20281019² = 822639463356722, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20280985 and 20281003.

It is not an unprimeable number, because it can be changed into a prime (20281013) 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, 86927 + ... + 87159.

It is an arithmetic number, because the mean of its divisors is an integer number (1429974).

Almost surely, 2^20281019 is an apocalyptic number.

20281019 is a deficient number, since it is larger than the sum of its proper divisors (2598565).

20281019 is a wasteful number, since it uses less digits than its factorization.

20281019 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 478.

The product of its (nonzero) digits is 288, while the sum is 23.

The square root of 20281019 is about 4503.4452367049. The cubic root of 20281019 is about 272.7071914137.

The spelling of 20281019 in words is "twenty million, two hundred eighty-one thousand, nineteen".