21220211122154 has 16 divisors (see below), whose sum is σ = 34733582182656. Its totient is φ = 9642883747200.

The previous prime is 21220211122153. The next prime is 21220211122211. The reversal of 21220211122154 is 45122111202212.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (21220211122153) 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, 133256762 + ... + 133415909.

It is an arithmetic number, because the mean of its divisors is an integer number (2170848886416).

Almost surely, 2^{21220211122154} is an apocalyptic number.

21220211122154 is a deficient number, since it is larger than the sum of its proper divisors (13513371060502).

21220211122154 is a wasteful number, since it uses less digits than its factorization.

21220211122154 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 266676301.

The product of its (nonzero) digits is 1280, while the sum is 26.

Adding to 21220211122154 its reverse (45122111202212), we get a palindrome (66342322324366).

The spelling of 21220211122154 in words is "twenty-one trillion, two hundred twenty billion, two hundred eleven million, one hundred twenty-two thousand, one hundred fifty-four".