20523021 has 8 divisors (see below), whose sum is σ = 28804320. Its totient is φ = 12961872.

The previous prime is 20522987. The next prime is 20523053. The reversal of 20523021 is 12032502.

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

It is not a de Polignac number, because 20523021 - 2¹³ = 20514829 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20523221) 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, 179970 + ... + 180083.

It is an arithmetic number, because the mean of its divisors is an integer number (3600540).

Almost surely, 2^20523021 is an apocalyptic number.

It is an amenable number.

20523021 is a deficient number, since it is larger than the sum of its proper divisors (8281299).

20523021 is a wasteful number, since it uses less digits than its factorization.

20523021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 360075.

The product of its (nonzero) digits is 120, while the sum is 15.

The square root of 20523021 is about 4530.2340999114. The cubic root of 20523021 is about 273.7875926773.

Adding to 20523021 its reverse (12032502), we get a palindrome (32555523).

The spelling of 20523021 in words is "twenty million, five hundred twenty-three thousand, twenty-one".