21111431204 has 6 divisors (see below), whose sum is σ = 36945004614. Its totient is φ = 10555715600.

The previous prime is 21111431191. The next prime is 21111431207. The reversal of 21111431204 is 40213411112.

It can be written as a sum of positive squares in only one way, i.e., 13261825600 + 7849605604 = 115160^2 + 88598^2 .

It is not an unprimeable number, because it can be changed into a prime (21111431207) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2638928897 + ... + 2638928904.

It is an arithmetic number, because the mean of its divisors is an integer number (6157500769).

Almost surely, 2^21111431204 is an apocalyptic number.

It is an amenable number.

21111431204 is a deficient number, since it is larger than the sum of its proper divisors (15833573410).

21111431204 is a wasteful number, since it uses less digits than its factorization.

21111431204 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5277857805 (or 5277857803 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 20.

Adding to 21111431204 its reverse (40213411112), we get a palindrome (61324842316).

The spelling of 21111431204 in words is "twenty-one billion, one hundred eleven million, four hundred thirty-one thousand, two hundred four".