21161376 has 36 divisors (see below), whose sum is σ = 60178482. Its totient is φ = 7053696.

The previous prime is 21161323. The next prime is 21161377. The reversal of 21161376 is 67316112.

It can be written as a sum of positive squares in only one way, i.e., 11048976 + 10112400 = 3324^2 + 3180^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is not an unprimeable number, because it can be changed into a prime (21161377) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 36451 + ... + 37026.

Almost surely, 2^21161376 is an apocalyptic number.

It is an amenable number.

21161376 is an abundant number, since it is smaller than the sum of its proper divisors (39017106).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21161376 is a wasteful number, since it uses less digits than its factorization.

21161376 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 73493 (or 73482 counting only the distinct ones).

The product of its digits is 1512, while the sum is 27.

The square root of 21161376 is about 4600.1495627860. The cubic root of 21161376 is about 276.5973200820.

Adding to 21161376 its reverse (67316112), we get a palindrome (88477488).

The spelling of 21161376 in words is "twenty-one million, one hundred sixty-one thousand, three hundred seventy-six".