21155143154320 has 80 divisors (see below), whose sum is σ = 58025535556608. Its totient is φ = 7019217999360.

The previous prime is 21155143154291. The next prime is 21155143154339. The reversal of 21155143154320 is 2345134155112.

It is a tau number, because it is divible by the number of its divisors (80).

It is a self number, because there is not a number n which added to its sum of digits gives 21155143154320.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 609289759 + ... + 609324478.

Almost surely, 2^{21155143154320} is an apocalyptic number.

21155143154320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21155143154320 is an abundant number, since it is smaller than the sum of its proper divisors (36870392402288).

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

21155143154320 is a wasteful number, since it uses less digits than its factorization.

21155143154320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1218614288 (or 1218614282 counting only the distinct ones).

The product of its (nonzero) digits is 72000, while the sum is 37.

The spelling of 21155143154320 in words is "twenty-one trillion, one hundred fifty-five billion, one hundred forty-three million, one hundred fifty-four thousand, three hundred twenty".