21512150444 has 24 divisors (see below), whose sum is σ = 38277164688. Its totient is φ = 10575944640.

The previous prime is 21512150431. The next prime is 21512150449. The reversal of 21512150444 is 44405121512.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (21512150449) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 737954 + ... + 766550.

It is an arithmetic number, because the mean of its divisors is an integer number (1594881862).

Almost surely, 2^21512150444 is an apocalyptic number.

It is an amenable number.

21512150444 is a deficient number, since it is larger than the sum of its proper divisors (16765014244).

21512150444 is a wasteful number, since it uses less digits than its factorization.

21512150444 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31745 (or 31743 counting only the distinct ones).

The product of its (nonzero) digits is 6400, while the sum is 29.

Adding to 21512150444 its reverse (44405121512), we get a palindrome (65917271956).

The spelling of 21512150444 in words is "twenty-one billion, five hundred twelve million, one hundred fifty thousand, four hundred forty-four".