21521352214 has 4 divisors (see below), whose sum is σ = 32282028324. Its totient is φ = 10760676106.

The previous prime is 21521352211. The next prime is 21521352247. The reversal of 21521352214 is 41225312512.

It is a happy number.

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

It is a super-2 number, since 2×21521352214² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21521352211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5380338052 + ... + 5380338055.

It is an arithmetic number, because the mean of its divisors is an integer number (8070507081).

Almost surely, 2^21521352214 is an apocalyptic number.

21521352214 is a deficient number, since it is larger than the sum of its proper divisors (10760676110).

21521352214 is a wasteful number, since it uses less digits than its factorization.

21521352214 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10760676109.

The product of its digits is 4800, while the sum is 28.

Adding to 21521352214 its reverse (41225312512), we get a palindrome (62746664726).

The spelling of 21521352214 in words is "twenty-one billion, five hundred twenty-one million, three hundred fifty-two thousand, two hundred fourteen".