20279513 has 4 divisors (see below), whose sum is σ = 20711040. Its totient is φ = 19847988.

The previous prime is 20279507. The next prime is 20279557. The reversal of 20279513 is 31597202.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20279513 - 2⁶ = 20279449 is a prime.

It is a super-2 number, since 2×20279513² = 822517295034338, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20279503) 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 3 ways as a sum of consecutive naturals, for example, 215693 + ... + 215786.

It is an arithmetic number, because the mean of its divisors is an integer number (5177760).

Almost surely, 2^20279513 is an apocalyptic number.

It is an amenable number.

20279513 is a deficient number, since it is larger than the sum of its proper divisors (431527).

20279513 is an equidigital number, since it uses as much as digits as its factorization.

20279513 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 431526.

The product of its (nonzero) digits is 3780, while the sum is 29.

The square root of 20279513 is about 4503.2780282812. The cubic root of 20279513 is about 272.7004411415.

The spelling of 20279513 in words is "twenty million, two hundred seventy-nine thousand, five hundred thirteen".