20279409 has 8 divisors (see below), whose sum is σ = 27132672. Its totient is φ = 13472880.

The previous prime is 20279401. The next prime is 20279411. The reversal of 20279409 is 90497202.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20279409 - 2³ = 20279401 is a prime.

It is a super-2 number, since 2×20279409² = 822508858778562, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 20279409.

It is not an unprimeable number, because it can be changed into a prime (20279401) 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, 10657 + ... + 12414.

It is an arithmetic number, because the mean of its divisors is an integer number (3391584).

Almost surely, 2^20279409 is an apocalyptic number.

It is an amenable number.

20279409 is a deficient number, since it is larger than the sum of its proper divisors (6853263).

20279409 is a wasteful number, since it uses less digits than its factorization.

20279409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23367.

The product of its (nonzero) digits is 9072, while the sum is 33.

The square root of 20279409 is about 4503.2664811223. The cubic root of 20279409 is about 272.6999749749.

The spelling of 20279409 in words is "twenty million, two hundred seventy-nine thousand, four hundred nine".