21045025551541 has 4 divisors (see below), whose sum is σ = 21155208931584. Its totient is φ = 20934842171500.

The previous prime is 21045025551527. The next prime is 21045025551601. The reversal of 21045025551541 is 14515552054012.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21045025551541 - 2¹⁹ = 21045025027253 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21045025551494 and 21045025551503.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21045025557541) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 55091689735 + ... + 55091690116.

It is an arithmetic number, because the mean of its divisors is an integer number (5288802232896).

Almost surely, 2^{21045025551541} is an apocalyptic number.

It is an amenable number.

21045025551541 is a deficient number, since it is larger than the sum of its proper divisors (110183380043).

21045025551541 is a wasteful number, since it uses less digits than its factorization.

21045025551541 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 110183380042.

The product of its (nonzero) digits is 200000, while the sum is 40.

The spelling of 21045025551541 in words is "twenty-one trillion, forty-five billion, twenty-five million, five hundred fifty-one thousand, five hundred forty-one".