21121221002 has 16 divisors (see below), whose sum is σ = 36215492352. Its totient is φ = 9050030640.

The previous prime is 21121221001. The next prime is 21121221013. The reversal of 21121221002 is 20012212112.

It is a super-2 number, since 2×21121221002² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (14).

It is not an unprimeable number, because it can be changed into a prime (21121221001) 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, 90749 + ... + 224672.

It is an arithmetic number, because the mean of its divisors is an integer number (2263468272).

Almost surely, 2^21121221002 is an apocalyptic number.

21121221002 is a deficient number, since it is larger than the sum of its proper divisors (15094271350).

21121221002 is a wasteful number, since it uses less digits than its factorization.

21121221002 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 320213.

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 21121221002 its reverse (20012212112), we get a palindrome (41133433114).

The spelling of 21121221002 in words is "twenty-one billion, one hundred twenty-one million, two hundred twenty-one thousand, two".