21021154 has 16 divisors (see below), whose sum is σ = 39312576. Its totient is φ = 8190000.

The previous prime is 21021127. The next prime is 21021157. The reversal of 21021154 is 45112012.

It is a super-3 number, since 3×21021154³ (a number of 23 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (21021157) 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, 68097 + ... + 68404.

It is an arithmetic number, because the mean of its divisors is an integer number (2457036).

Almost surely, 2^21021154 is an apocalyptic number.

21021154 is a deficient number, since it is larger than the sum of its proper divisors (18291422).

21021154 is a wasteful number, since it uses less digits than its factorization.

21021154 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 136521.

The product of its (nonzero) digits is 80, while the sum is 16.

The square root of 21021154 is about 4584.8832046193. The cubic root of 21021154 is about 275.9850250924.

Adding to 21021154 its reverse (45112012), we get a palindrome (66133166).

The spelling of 21021154 in words is "twenty-one million, twenty-one thousand, one hundred fifty-four".