20021534 has 8 divisors (see below), whose sum is σ = 32342520. Its totient is φ = 9240696.

The previous prime is 20021527. The next prime is 20021537. The reversal of 20021534 is 43512002.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20021537) 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, 385004 + ... + 385055.

It is an arithmetic number, because the mean of its divisors is an integer number (4042815).

Almost surely, 2^20021534 is an apocalyptic number.

20021534 is a deficient number, since it is larger than the sum of its proper divisors (12320986).

20021534 is a wasteful number, since it uses less digits than its factorization.

20021534 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 770074.

The product of its (nonzero) digits is 240, while the sum is 17.

The square root of 20021534 is about 4474.5428816808. The cubic root of 20021534 is about 271.5391471645.

Adding to 20021534 its reverse (43512002), we get a palindrome (63533536).

The spelling of 20021534 in words is "twenty million, twenty-one thousand, five hundred thirty-four".