20021001011 has 4 divisors (see below), whose sum is σ = 21841092024. Its totient is φ = 18200910000.

The previous prime is 20021000981. The next prime is 20021001029. The reversal of 20021001011 is 11010012002.

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

It is a cyclic number.

It is not a de Polignac number, because 20021001011 - 2²² = 20016806707 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20021001011.

It is not an unprimeable number, because it can be changed into a prime (20021001311) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 910045490 + ... + 910045511.

It is an arithmetic number, because the mean of its divisors is an integer number (5460273006).

Almost surely, 2^20021001011 is an apocalyptic number.

20021001011 is a deficient number, since it is larger than the sum of its proper divisors (1820091013).

20021001011 is a wasteful number, since it uses less digits than its factorization.

20021001011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1820091012.

The product of its (nonzero) digits is 4, while the sum is 8.

Adding to 20021001011 its reverse (11010012002), we get a palindrome (31031013013).

The spelling of 20021001011 in words is "twenty billion, twenty-one million, one thousand, eleven".