20021220727 has 4 divisors (see below), whose sum is σ = 20065031296. Its totient is φ = 19977410160.

The previous prime is 20021220707. The next prime is 20021220763. The reversal of 20021220727 is 72702212002.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20021220727 is a prime.

It is a super-3 number, since 3×20021220727³ (a number of 32 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20021220707) 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, 21904599 + ... + 21905512.

It is an arithmetic number, because the mean of its divisors is an integer number (5016257824).

Almost surely, 2^20021220727 is an apocalyptic number.

20021220727 is a deficient number, since it is larger than the sum of its proper divisors (43810569).

20021220727 is an equidigital number, since it uses as much as digits as its factorization.

20021220727 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43810568.

The product of its (nonzero) digits is 1568, while the sum is 25.

Adding to 20021220727 its reverse (72702212002), we get a palindrome (92723432729).

The spelling of 20021220727 in words is "twenty billion, twenty-one million, two hundred twenty thousand, seven hundred twenty-seven".