21510152 has 16 divisors (see below), whose sum is σ = 42085440. Its totient is φ = 10287376.

The previous prime is 21510133. The next prime is 21510157. The reversal of 21510152 is 25101512.

It is a self number, because there is not a number n which added to its sum of digits gives 21510152.

It is not an unprimeable number, because it can be changed into a prime (21510157) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 58268 + ... + 58635.

It is an arithmetic number, because the mean of its divisors is an integer number (2630340).

Almost surely, 2^21510152 is an apocalyptic number.

It is an amenable number.

21510152 is a deficient number, since it is larger than the sum of its proper divisors (20575288).

21510152 is a wasteful number, since it uses less digits than its factorization.

21510152 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 116932 (or 116928 counting only the distinct ones).

The product of its (nonzero) digits is 100, while the sum is 17.

The square root of 21510152 is about 4637.9038368642. The cubic root of 21510152 is about 278.1086475594.

Adding to 21510152 its reverse (25101512), we get a palindrome (46611664).

The spelling of 21510152 in words is "twenty-one million, five hundred ten thousand, one hundred fifty-two".