21557172141 has 32 divisors (see below), whose sum is σ = 33090768000. Its totient is φ = 13861246464.

The previous prime is 21557172137. The next prime is 21557172149. The reversal of 21557172141 is 14127175512.

It is a happy number.

21557172141 is a `hidden beast` number, since 2 + 1 + 5 + 571 + 72 + 14 + 1 = 666.

It is not a de Polignac number, because 21557172141 - 2² = 21557172137 is a prime.

It is a super-3 number, since 3×21557172141³ (a number of 32 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21557172096 and 21557172105.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21557172149) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 43236 + ... + 212093.

It is an arithmetic number, because the mean of its divisors is an integer number (1034086500).

Almost surely, 2^21557172141 is an apocalyptic number.

It is an amenable number.

21557172141 is a deficient number, since it is larger than the sum of its proper divisors (11533595859).

21557172141 is a wasteful number, since it uses less digits than its factorization.

21557172141 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 255450 (or 255444 counting only the distinct ones).

The product of its digits is 19600, while the sum is 36.

The spelling of 21557172141 in words is "twenty-one billion, five hundred fifty-seven million, one hundred seventy-two thousand, one hundred forty-one".