21347554 has 8 divisors (see below), whose sum is σ = 32106960. Its totient is φ = 10645236.

The previous prime is 21347551. The next prime is 21347569. The reversal of 21347554 is 45574312.

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

It is not an unprimeable number, because it can be changed into a prime (21347551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13324 + ... + 14839.

It is an arithmetic number, because the mean of its divisors is an integer number (4013370).

Almost surely, 2^21347554 is an apocalyptic number.

21347554 is a deficient number, since it is larger than the sum of its proper divisors (10759406).

21347554 is a wasteful number, since it uses less digits than its factorization.

21347554 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28544.

The product of its digits is 16800, while the sum is 31.

The square root of 21347554 is about 4620.3413293825. The cubic root of 21347554 is about 277.4061214246.

The spelling of 21347554 in words is "twenty-one million, three hundred forty-seven thousand, five hundred fifty-four".