21155143645146 has 128 divisors (see below), whose sum is σ = 50734231358976. Its totient is φ = 5754527400960.

The previous prime is 21155143645087. The next prime is 21155143645169. The reversal of 21155143645146 is 64154634155112.

It is a super-2 number, since 2×21155143645146² (a number of 27 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21155143645095 and 21155143645104.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 30376716 + ... + 31065336.

It is an arithmetic number, because the mean of its divisors is an integer number (396361182492).

Almost surely, 2^{21155143645146} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21155143645146, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25367115679488).

21155143645146 is an abundant number, since it is smaller than the sum of its proper divisors (29579087713830).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21155143645146 is a wasteful number, since it uses less digits than its factorization.

21155143645146 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 689096.

The product of its digits is 1728000, while the sum is 48.

The spelling of 21155143645146 in words is "twenty-one trillion, one hundred fifty-five billion, one hundred forty-three million, six hundred forty-five thousand, one hundred forty-six".