20523513 has 8 divisors (see below), whose sum is σ = 28001248. Its totient is φ = 13364064.

The previous prime is 20523499. The next prime is 20523527. The reversal of 20523513 is 31532502.

It is an interprime number because it is at equal distance from previous prime (20523499) and next prime (20523527).

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

It is not a de Polignac number, because 20523513 - 2⁴ = 20523497 is a prime.

It is a super-2 number, since 2×20523513² = 842429171722338, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20523513.

It is not an unprimeable number, because it can be changed into a prime (20523533) 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, 79420 + ... + 79677.

It is an arithmetic number, because the mean of its divisors is an integer number (3500156).

Almost surely, 2^20523513 is an apocalyptic number.

It is an amenable number.

20523513 is a deficient number, since it is larger than the sum of its proper divisors (7477735).

20523513 is a wasteful number, since it uses less digits than its factorization.

20523513 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 159143.

The product of its (nonzero) digits is 900, while the sum is 21.

The square root of 20523513 is about 4530.2884014155. The cubic root of 20523513 is about 273.7897805036.

It can be divided in two parts, 2052 and 3513, that added together give a triangular number (5565 = T₁₀₅).

The spelling of 20523513 in words is "twenty million, five hundred twenty-three thousand, five hundred thirteen".