21033115450 has 24 divisors (see below), whose sum is σ = 39144486780. Its totient is φ = 8408323200.

The previous prime is 21033115427. The next prime is 21033115459. The reversal of 21033115450 is 5451133012.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 12792288609 + 8240826841 = 113103^2 + 90779^2 .

It is a Harshad number since it is a multiple of its sum of digits (25).

It is not an unprimeable number, because it can be changed into a prime (21033115459) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 36165 + ... + 208264.

Almost surely, 2^21033115450 is an apocalyptic number.

21033115450 is a deficient number, since it is larger than the sum of its proper divisors (18111371330).

21033115450 is a wasteful number, since it uses less digits than its factorization.

21033115450 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 246162 (or 246157 counting only the distinct ones).

The product of its (nonzero) digits is 1800, while the sum is 25.

Adding to 21033115450 its reverse (5451133012), we get a palindrome (26484248462).

The spelling of 21033115450 in words is "twenty-one billion, thirty-three million, one hundred fifteen thousand, four hundred fifty".