21152075 has 36 divisors (see below), whose sum is σ = 31551552. Its totient is φ = 14011200.

The previous prime is 21152069. The next prime is 21152077. The reversal of 21152075 is 57025112.

It is a happy number.

It is not a de Polignac number, because 21152075 - 2⁶ = 21152011 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21152075.

It is not an unprimeable number, because it can be changed into a prime (21152077) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 37697 + ... + 38253.

It is an arithmetic number, because the mean of its divisors is an integer number (876432).

Almost surely, 2^21152075 is an apocalyptic number.

21152075 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21152075 is a deficient number, since it is larger than the sum of its proper divisors (10399477).

21152075 is a wasteful number, since it uses less digits than its factorization.

21152075 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 612 (or 600 counting only the distinct ones).

The product of its (nonzero) digits is 700, while the sum is 23.

The square root of 21152075 is about 4599.1385062857. The cubic root of 21152075 is about 276.5567901297.

Adding to 21152075 its reverse (57025112), we get a palindrome (78177187).

The spelling of 21152075 in words is "twenty-one million, one hundred fifty-two thousand, seventy-five".