20521430045 has 8 divisors (see below), whose sum is σ = 24714619224. Its totient is φ = 16357875264.

The previous prime is 20521430011. The next prime is 20521430057. The reversal of 20521430045 is 54003412502.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 5135012281 + 15386417764 = 71659^2 + 124042^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20521430045 - 2²² = 20517235741 is a prime.

It is a super-2 number, since 2×20521430045² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20521429996 and 20521430023.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7407074 + ... + 7409843.

It is an arithmetic number, because the mean of its divisors is an integer number (3089327403).

Almost surely, 2^20521430045 is an apocalyptic number.

It is an amenable number.

20521430045 is a deficient number, since it is larger than the sum of its proper divisors (4193189179).

20521430045 is a wasteful number, since it uses less digits than its factorization.

20521430045 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14817199.

The product of its (nonzero) digits is 4800, while the sum is 26.

Adding to 20521430045 its reverse (54003412502), we get a palindrome (74524842547).

The spelling of 20521430045 in words is "twenty billion, five hundred twenty-one million, four hundred thirty thousand, forty-five".