21101456 has 10 divisors (see below), whose sum is σ = 40884102. Its totient is φ = 10550720.

The previous prime is 21101441. The next prime is 21101459. The reversal of 21101456 is 65410112.

It can be written as a sum of positive squares in only one way, i.e., 18490000 + 2611456 = 4300^2 + 1616^2 .

It is not an unprimeable number, because it can be changed into a prime (21101459) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 659405 + ... + 659436.

Almost surely, 2^21101456 is an apocalyptic number.

It is an amenable number.

21101456 is a deficient number, since it is larger than the sum of its proper divisors (19782646).

21101456 is a wasteful number, since it uses less digits than its factorization.

21101456 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1318849 (or 1318843 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 20.

The square root of 21101456 is about 4593.6321141337. The cubic root of 21101456 is about 276.3360046977.

Adding to 21101456 its reverse (65410112), we get a palindrome (86511568).

The spelling of 21101456 in words is "twenty-one million, one hundred one thousand, four hundred fifty-six".