21147450 has 24 divisors (see below), whose sum is σ = 52446048. Its totient is φ = 5639280.

The previous prime is 21147433. The next prime is 21147479. The reversal of 21147450 is 5474112.

It is a self number, because there is not a number n which added to its sum of digits gives 21147450.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 70342 + ... + 70641.

It is an arithmetic number, because the mean of its divisors is an integer number (2185252).

Almost surely, 2^21147450 is an apocalyptic number.

21147450 is an abundant number, since it is smaller than the sum of its proper divisors (31298598).

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

21147450 is a wasteful number, since it uses less digits than its factorization.

21147450 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 140998 (or 140993 counting only the distinct ones).

The product of its (nonzero) digits is 1120, while the sum is 24.

The square root of 21147450 is about 4598.6356672387. The cubic root of 21147450 is about 276.5366318491.

The spelling of 21147450 in words is "twenty-one million, one hundred forty-seven thousand, four hundred fifty".