21154234 has 8 divisors (see below), whose sum is σ = 31751028. Its totient is φ = 10570560.

The previous prime is 21154207. The next prime is 21154283. The reversal of 21154234 is 43245112.

It can be written as a sum of positive squares in 2 ways, for example, as 20223009 + 931225 = 4497^2 + 965^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×21154234² = 895003232253512, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3874 + ... + 7570.

Almost surely, 2^21154234 is an apocalyptic number.

21154234 is a deficient number, since it is larger than the sum of its proper divisors (10596794).

21154234 is a wasteful number, since it uses less digits than its factorization.

21154234 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6560.

The product of its digits is 960, while the sum is 22.

The square root of 21154234 is about 4599.3732181679. The cubic root of 21154234 is about 276.5661992270.

Adding to 21154234 its reverse (43245112), we get a palindrome (64399346).

It can be divided in two parts, 211 and 54234, that added together give a palindrome (54445).

The spelling of 21154234 in words is "twenty-one million, one hundred fifty-four thousand, two hundred thirty-four".