21121221410 has 16 divisors (see below), whose sum is σ = 38317556736. Its totient is φ = 8381964528.

The previous prime is 21121221367. The next prime is 21121221419. The reversal of 21121221410 is 1412212112.

It is a super-2 number, since 2×21121221410² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21121221419) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8314172 + ... + 8316711.

It is an arithmetic number, because the mean of its divisors is an integer number (2394847296).

Almost surely, 2^21121221410 is an apocalyptic number.

21121221410 is a deficient number, since it is larger than the sum of its proper divisors (17196335326).

21121221410 is a wasteful number, since it uses less digits than its factorization.

21121221410 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16631017.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 21121221410 its reverse (1412212112), we get a palindrome (22533433522).

The spelling of 21121221410 in words is "twenty-one billion, one hundred twenty-one million, two hundred twenty-one thousand, four hundred ten".