21373266042 has 20 divisors (see below), whose sum is σ = 47891948346. Its totient is φ = 7124421960.

The previous prime is 21373266037. The next prime is 21373266049. The reversal of 21373266042 is 24066237312.

21373266042 is a `hidden beast` number, since 2 + 13 + 7 + 32 + 6 + 604 + 2 = 666.

It can be written as a sum of positive squares in only one way, i.e., 16151613921 + 5221652121 = 127089^2 + 72261^2 .

It is a super-2 number, since 2×21373266042² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21373265988 and 21373266006.

It is not an unprimeable number, because it can be changed into a prime (21373266049) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 65966709 + ... + 65967032.

Almost surely, 2^21373266042 is an apocalyptic number.

21373266042 is an abundant number, since it is smaller than the sum of its proper divisors (26518682304).

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

21373266042 is a wasteful number, since it uses less digits than its factorization.

21373266042 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 131933755 (or 131933746 counting only the distinct ones).

The product of its (nonzero) digits is 72576, while the sum is 36.

The spelling of 21373266042 in words is "twenty-one billion, three hundred seventy-three million, two hundred sixty-six thousand, forty-two".