20121231436 has 6 divisors (see below), whose sum is σ = 35212155020. Its totient is φ = 10060615716.

The previous prime is 20121231409. The next prime is 20121231437. The reversal of 20121231436 is 63413212102.

It is a self number, because there is not a number n which added to its sum of digits gives 20121231436.

It is not an unprimeable number, because it can be changed into a prime (20121231437) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2515153926 + ... + 2515153933.

Almost surely, 2^20121231436 is an apocalyptic number.

It is an amenable number.

20121231436 is a deficient number, since it is larger than the sum of its proper divisors (15090923584).

20121231436 is a wasteful number, since it uses less digits than its factorization.

20121231436 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5030307863 (or 5030307861 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 25.

Adding to 20121231436 its reverse (63413212102), we get a palindrome (83534443538).

The spelling of 20121231436 in words is "twenty billion, one hundred twenty-one million, two hundred thirty-one thousand, four hundred thirty-six".