21154330 has 8 divisors (see below), whose sum is σ = 38077812. Its totient is φ = 8461728.

The previous prime is 21154283. The next prime is 21154339. The reversal of 21154330 is 3345112.

It can be written as a sum of positive squares in 2 ways, for example, as 18584721 + 2569609 = 4311^2 + 1603^2 .

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

It is a junction number, because it is equal to n+sod(n) for n = 21154298 and 21154307.

It is not an unprimeable number, because it can be changed into a prime (21154339) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1057707 + ... + 1057726.

Almost surely, 2^21154330 is an apocalyptic number.

21154330 is a deficient number, since it is larger than the sum of its proper divisors (16923482).

21154330 is a wasteful number, since it uses less digits than its factorization.

21154330 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2115440.

The product of its (nonzero) digits is 360, while the sum is 19.

The square root of 21154330 is about 4599.3836543607. The cubic root of 21154330 is about 276.5666175879.

Adding to 21154330 its reverse (3345112), we get a palindrome (24499442).

The spelling of 21154330 in words is "twenty-one million, one hundred fifty-four thousand, three hundred thirty".