21440000156 has 12 divisors (see below), whose sum is σ = 37768478160. Its totient is φ = 10649006400.

The previous prime is 21440000111. The next prime is 21440000189. The reversal of 21440000156 is 65100004412.

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, 17747741 + ... + 17748948.

It is an arithmetic number, because the mean of its divisors is an integer number (3147373180).

Almost surely, 2^21440000156 is an apocalyptic number.

It is an amenable number.

21440000156 is a deficient number, since it is larger than the sum of its proper divisors (16328478004).

21440000156 is a wasteful number, since it uses less digits than its factorization.

21440000156 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35496844 (or 35496842 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 23.

Adding to 21440000156 its reverse (65100004412), we get a palindrome (86540004568).

The spelling of 21440000156 in words is "twenty-one billion, four hundred forty million, one hundred fifty-six", and thus it is an aban number.