21155166222052 has 6 divisors (see below), whose sum is σ = 37021540888598. Its totient is φ = 10577583111024.

The previous prime is 21155166222023. The next prime is 21155166222121. The reversal of 21155166222052 is 25022266155112.

It can be written as a sum of positive squares in only one way, i.e., 20562179978916 + 592986243136 = 4534554^2 + 770056^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21155166221996 and 21155166222014.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2644395777753 + ... + 2644395777760.

Almost surely, 2^{21155166222052} is an apocalyptic number.

It is an amenable number.

21155166222052 is a deficient number, since it is larger than the sum of its proper divisors (15866374666546).

21155166222052 is a wasteful number, since it uses less digits than its factorization.

21155166222052 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5288791555517 (or 5288791555515 counting only the distinct ones).

The product of its (nonzero) digits is 144000, while the sum is 40.

The spelling of 21155166222052 in words is "twenty-one trillion, one hundred fifty-five billion, one hundred sixty-six million, two hundred twenty-two thousand, fifty-two".