20721027 has 8 divisors (see below), whose sum is σ = 27654480. Its totient is φ = 13800800.

The previous prime is 20721013. The next prime is 20721037. The reversal of 20721027 is 72012702.

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

It is a cyclic number.

It is not a de Polignac number, because 20721027 - 2⁷ = 20720899 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20720994 and 20721012.

It is not an unprimeable number, because it can be changed into a prime (20721037) 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, 1249 + ... + 6557.

It is an arithmetic number, because the mean of its divisors is an integer number (3456810).

Almost surely, 2^20721027 is an apocalyptic number.

20721027 is a deficient number, since it is larger than the sum of its proper divisors (6933453).

20721027 is a wasteful number, since it uses less digits than its factorization.

20721027 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6613.

The product of its (nonzero) digits is 392, while the sum is 21.

The square root of 20721027 is about 4552.0354787721. The cubic root of 20721027 is about 274.6652764943.

Adding to 20721027 its reverse (72012702), we get a palindrome (92733729).

The spelling of 20721027 in words is "twenty million, seven hundred twenty-one thousand, twenty-seven".