211221000023 has 4 divisors (see below), whose sum is σ = 230422909128. Its totient is φ = 192019090920.

The previous prime is 211221000017. The next prime is 211221000037. The reversal of 211221000023 is 320000122112.

It is a happy number.

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 211221000023 - 2¹² = 211220995927 is a prime.

It is a super-2 number, since 2×211221000023² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 211220999971 and 211221000007.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211221000323) 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, 9600954536 + ... + 9600954557.

It is an arithmetic number, because the mean of its divisors is an integer number (57605727282).

Almost surely, 2^211221000023 is an apocalyptic number.

211221000023 is a deficient number, since it is larger than the sum of its proper divisors (19201909105).

211221000023 is a wasteful number, since it uses less digits than its factorization.

211221000023 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19201909104.

The product of its (nonzero) digits is 48, while the sum is 14.

Adding to 211221000023 its reverse (320000122112), we get a palindrome (531221122135).

The spelling of 211221000023 in words is "two hundred eleven billion, two hundred twenty-one million, twenty-three", and thus it is an aban number.