20015303645 has 4 divisors (see below), whose sum is σ = 24018364380. Its totient is φ = 16012242912.

The previous prime is 20015303629. The next prime is 20015303657. The reversal of 20015303645 is 54630351002.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 54630351002 = 2 ⋅27315175501.

It can be written as a sum of positive squares in 2 ways, for example, as 8134957636 + 11880346009 = 90194^2 + 108997^2 .

It is a cyclic number.

It is not a de Polignac number, because 20015303645 - 2⁴ = 20015303629 is a prime.

It is a super-2 number, since 2×20015303645² (a number of 21 digits) contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2001530360 + ... + 2001530369.

It is an arithmetic number, because the mean of its divisors is an integer number (6004591095).

Almost surely, 2^20015303645 is an apocalyptic number.

It is an amenable number.

20015303645 is a deficient number, since it is larger than the sum of its proper divisors (4003060735).

20015303645 is an equidigital number, since it uses as much as digits as its factorization.

20015303645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4003060734.

The product of its (nonzero) digits is 10800, while the sum is 29.

Adding to 20015303645 its reverse (54630351002), we get a palindrome (74645654647).

The spelling of 20015303645 in words is "twenty billion, fifteen million, three hundred three thousand, six hundred forty-five".