21161488 has 10 divisors (see below), whose sum is σ = 41000414. Its totient is φ = 10580736.

The previous prime is 21161467. The next prime is 21161489. The reversal of 21161488 is 88416112.

It can be written as a sum of positive squares in only one way, i.e., 12588304 + 8573184 = 3548^2 + 2928^2 .

It is not an unprimeable number, because it can be changed into a prime (21161489) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 661281 + ... + 661312.

Almost surely, 2^21161488 is an apocalyptic number.

It is an amenable number.

21161488 is a deficient number, since it is larger than the sum of its proper divisors (19838926).

21161488 is a wasteful number, since it uses less digits than its factorization.

21161488 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1322601 (or 1322595 counting only the distinct ones).

The product of its digits is 3072, while the sum is 31.

The square root of 21161488 is about 4600.1617362871. The cubic root of 21161488 is about 276.5978080598.

The spelling of 21161488 in words is "twenty-one million, one hundred sixty-one thousand, four hundred eighty-eight".