21450234 has 16 divisors (see below), whose sum is σ = 46200672. Its totient is φ = 6600048.

The previous prime is 21450229. The next prime is 21450239. The reversal of 21450234 is 43205412.

It is an interprime number because it is at equal distance from previous prime (21450229) and next prime (21450239).

It is a super-2 number, since 2×21450234² = 920225077309512, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21450234.

It is not an unprimeable number, because it can be changed into a prime (21450239) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 137424 + ... + 137579.

It is an arithmetic number, because the mean of its divisors is an integer number (2887542).

Almost surely, 2^21450234 is an apocalyptic number.

21450234 is an abundant number, since it is smaller than the sum of its proper divisors (24750438).

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

21450234 is a wasteful number, since it uses less digits than its factorization.

21450234 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 275021.

The product of its (nonzero) digits is 960, while the sum is 21.

The square root of 21450234 is about 4631.4397329556. The cubic root of 21450234 is about 277.8501771935.

Adding to 21450234 its reverse (43205412), we get a palindrome (64655646).

The spelling of 21450234 in words is "twenty-one million, four hundred fifty thousand, two hundred thirty-four".