21480136 has 8 divisors (see below), whose sum is σ = 40275270. Its totient is φ = 10740064.

The previous prime is 21480131. The next prime is 21480157. The reversal of 21480136 is 63108412.

It can be written as a sum of positive squares in only one way, i.e., 17892900 + 3587236 = 4230^2 + 1894^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a super-2 number, since 2×21480136² = 922792485156992, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21480136.

It is not an unprimeable number, because it can be changed into a prime (21480131) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1342501 + ... + 1342516.

Almost surely, 2^21480136 is an apocalyptic number.

It is an amenable number.

21480136 is a deficient number, since it is larger than the sum of its proper divisors (18795134).

21480136 is a wasteful number, since it uses less digits than its factorization.

21480136 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2685023 (or 2685019 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 25.

The square root of 21480136 is about 4634.6667625623. Note that the first 3 decimals coincide. The cubic root of 21480136 is about 277.9792265760.

Adding to 21480136 its reverse (63108412), we get a palindrome (84588548).

The spelling of 21480136 in words is "twenty-one million, four hundred eighty thousand, one hundred thirty-six".