21700250 has 64 divisors (see below), whose sum is σ = 47803392. Its totient is φ = 7272000.

The previous prime is 21700243. The next prime is 21700253. The reversal of 21700250 is 5200712.

It is not an unprimeable number, because it can be changed into a prime (21700253) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 35447 + ... + 36053.

It is an arithmetic number, because the mean of its divisors is an integer number (746928).

Almost surely, 2^21700250 is an apocalyptic number.

21700250 is an abundant number, since it is smaller than the sum of its proper divisors (26103142).

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

21700250 is a wasteful number, since it uses less digits than its factorization.

21700250 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 648 (or 638 counting only the distinct ones).

The product of its (nonzero) digits is 140, while the sum is 17.

The square root of 21700250 is about 4658.3527131380. The cubic root of 21700250 is about 278.9255163598.

Adding to 21700250 its reverse (5200712), we get a palindrome (26900962).

The spelling of 21700250 in words is "twenty-one million, seven hundred thousand, two hundred fifty".