21220104951 has 16 divisors (see below), whose sum is σ = 33091782400. Its totient is φ = 13402171224.

The previous prime is 21220104943. The next prime is 21220105013. The reversal of 21220104951 is 15940102212.

It is not a de Polignac number, because 21220104951 - 2³ = 21220104943 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21220104901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 20681851 + ... + 20682876.

It is an arithmetic number, because the mean of its divisors is an integer number (2068236400).

Almost surely, 2^21220104951 is an apocalyptic number.

21220104951 is a deficient number, since it is larger than the sum of its proper divisors (11871677449).

21220104951 is a wasteful number, since it uses less digits than its factorization.

21220104951 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41364755 (or 41364749 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 27.

The spelling of 21220104951 in words is "twenty-one billion, two hundred twenty million, one hundred four thousand, nine hundred fifty-one".