21155142253525 has 48 divisors (see below), whose sum is σ = 30586199643648. Its totient is φ = 14213721600000.

The previous prime is 21155142253499. The next prime is 21155142253579. The reversal of 21155142253525 is 52535224155112.

It is not a de Polignac number, because 21155142253525 - 2²⁷ = 21155008035797 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 5446965 + ... + 8484085.

It is an arithmetic number, because the mean of its divisors is an integer number (637212492576).

Almost surely, 2^{21155142253525} is an apocalyptic number.

21155142253525 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21155142253525 is a deficient number, since it is larger than the sum of its proper divisors (9431057390123).

21155142253525 is a wasteful number, since it uses less digits than its factorization.

21155142253525 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3037942 (or 3037937 counting only the distinct ones).

The product of its digits is 600000, while the sum is 43.

The spelling of 21155142253525 in words is "twenty-one trillion, one hundred fifty-five billion, one hundred forty-two million, two hundred fifty-three thousand, five hundred twenty-five".