21122020345 has 64 divisors (see below), whose sum is σ = 28314703872. Its totient is φ = 15054336000.

The previous prime is 21122020333. The next prime is 21122020349. The reversal of 21122020345 is 54302022112.

It is a happy number.

It is not a de Polignac number, because 21122020345 - 2¹¹ = 21122018297 is a prime.

It is a super-2 number, since 2×21122020345² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21122020349) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 31954315 + ... + 31954975.

It is an arithmetic number, because the mean of its divisors is an integer number (442417248).

Almost surely, 2^21122020345 is an apocalyptic number.

It is an amenable number.

21122020345 is a deficient number, since it is larger than the sum of its proper divisors (7192683527).

21122020345 is a wasteful number, since it uses less digits than its factorization.

21122020345 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 962.

The product of its (nonzero) digits is 960, while the sum is 22.

Adding to 21122020345 its reverse (54302022112), we get a palindrome (75424042457).

The spelling of 21122020345 in words is "twenty-one billion, one hundred twenty-two million, twenty thousand, three hundred forty-five".