21394541052 has 18 divisors (see below), whose sum is σ = 54080645528. Its totient is φ = 7131513672.

The previous prime is 21394541023. The next prime is 21394541057. The reversal of 21394541052 is 25014549312.

21394541052 is a `hidden beast` number, since 21 + 3 + 94 + 541 + 0 + 5 + 2 = 666.

It is a tau number, because it is divible by the number of its divisors (18).

It is a Harshad number since it is a multiple of its sum of digits (36), and also a Moran number because the ratio is a prime number: 594292807 = 21394541052 / (2 + 1 + 3 + 9 + 4 + 5 + 4 + 1 + 0 + 5 + 2).

It is a junction number, because it is equal to n+sod(n) for n = 21394540998 and 21394541016.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21394541057) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 297146368 + ... + 297146439.

Almost surely, 2^21394541052 is an apocalyptic number.

It is an amenable number.

21394541052 is an abundant number, since it is smaller than the sum of its proper divisors (32686104476).

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

21394541052 is a wasteful number, since it uses less digits than its factorization.

21394541052 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 594292817 (or 594292812 counting only the distinct ones).

The product of its (nonzero) digits is 43200, while the sum is 36.

The spelling of 21394541052 in words is "twenty-one billion, three hundred ninety-four million, five hundred forty-one thousand, fifty-two".