21854070 has 128 divisors (see below), whose sum is σ = 68935680. Its totient is φ = 4821120.

The previous prime is 21854059. The next prime is 21854089. The reversal of 21854070 is 7045812.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 58404 + ... + 58776.

It is an arithmetic number, because the mean of its divisors is an integer number (538560).

Almost surely, 2^21854070 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21854070, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34467840).

21854070 is an abundant number, since it is smaller than the sum of its proper divisors (47081610).

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

21854070 is a wasteful number, since it uses less digits than its factorization.

21854070 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 427 (or 421 counting only the distinct ones).

The product of its (nonzero) digits is 2240, while the sum is 27.

The square root of 21854070 is about 4674.8336868813. The cubic root of 21854070 is about 279.5830102591.

Adding to 21854070 its reverse (7045812), we get a palindrome (28899882).

The spelling of 21854070 in words is "twenty-one million, eight hundred fifty-four thousand, seventy".