21211291522 has 4 divisors (see below), whose sum is σ = 31816937286. Its totient is φ = 10605645760.

The previous prime is 21211291511. The next prime is 21211291523. The reversal of 21211291522 is 22519211212.

It is a happy number.

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

It can be written as a sum of positive squares in only one way, i.e., 20457294841 + 753996681 = 143029^2 + 27459^2 .

It is not an unprimeable number, because it can be changed into a prime (21211291523) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5302822879 + ... + 5302822882.

Almost surely, 2^21211291522 is an apocalyptic number.

21211291522 is a deficient number, since it is larger than the sum of its proper divisors (10605645764).

21211291522 is a wasteful number, since it uses less digits than its factorization.

21211291522 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10605645763.

The product of its digits is 1440, while the sum is 28.

The spelling of 21211291522 in words is "twenty-one billion, two hundred eleven million, two hundred ninety-one thousand, five hundred twenty-two".