20401012243 has 4 divisors (see below), whose sum is σ = 20401300480. Its totient is φ = 20400724008.

The previous prime is 20401012211. The next prime is 20401012267. The reversal of 20401012243 is 34221010402.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 20401012243 - 2⁵ = 20401012211 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20401012243.

It is not an unprimeable number, because it can be changed into a prime (20401012283) 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, 43246 + ... + 206572.

It is an arithmetic number, because the mean of its divisors is an integer number (5100325120).

Almost surely, 2^20401012243 is an apocalyptic number.

20401012243 is a deficient number, since it is larger than the sum of its proper divisors (288237).

20401012243 is a wasteful number, since it uses less digits than its factorization.

20401012243 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 288236.

The product of its (nonzero) digits is 384, while the sum is 19.

Adding to 20401012243 its reverse (34221010402), we get a palindrome (54622022645).

The spelling of 20401012243 in words is "twenty billion, four hundred one million, twelve thousand, two hundred forty-three".