20415521232011 has 4 divisors (see below), whose sum is σ = 21119504722800. Its totient is φ = 19711537741224.

The previous prime is 20415521231981. The next prime is 20415521232049. The reversal of 20415521232011 is 11023212551402.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20415521232011 is a prime.

It is a super-2 number, since 2×20415521232011² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (29), and also a Moran number because the ratio is a prime number: 703983490759 = 20415521232011 / (2 + 0 + 4 + 1 + 5 + 5 + 2 + 1 + 2 + 3 + 2 + 0 + 1 + 1).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20415521232061) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 351991745351 + ... + 351991745408.

It is an arithmetic number, because the mean of its divisors is an integer number (5279876180700).

Almost surely, 2^{20415521232011} is an apocalyptic number.

20415521232011 is a deficient number, since it is larger than the sum of its proper divisors (703983490789).

20415521232011 is an equidigital number, since it uses as much as digits as its factorization.

20415521232011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 703983490788.

The product of its (nonzero) digits is 4800, while the sum is 29.

Adding to 20415521232011 its reverse (11023212551402), we get a palindrome (31438733783413).

The spelling of 20415521232011 in words is "twenty trillion, four hundred fifteen billion, five hundred twenty-one million, two hundred thirty-two thousand, eleven".