20529257 has 4 divisors (see below), whose sum is σ = 23462016. Its totient is φ = 17596500.

The previous prime is 20529221. The next prime is 20529259. The reversal of 20529257 is 75292502.

It is a happy number.

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 20529257 - 2²² = 16334953 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20529259) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1466369 + ... + 1466382.

It is an arithmetic number, because the mean of its divisors is an integer number (5865504).

Almost surely, 2^20529257 is an apocalyptic number.

It is an amenable number.

20529257 is a deficient number, since it is larger than the sum of its proper divisors (2932759).

20529257 is an equidigital number, since it uses as much as digits as its factorization.

20529257 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2932758.

The product of its (nonzero) digits is 12600, while the sum is 32.

The square root of 20529257 is about 4530.9223122892. The cubic root of 20529257 is about 273.8153203451.

The spelling of 20529257 in words is "twenty million, five hundred twenty-nine thousand, two hundred fifty-seven".