21355401 has 8 divisors (see below), whose sum is σ = 29243584. Its totient is φ = 13852080.

The previous prime is 21355393. The next prime is 21355403. The reversal of 21355401 is 10455312.

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

It is not a de Polignac number, because 21355401 - 2³ = 21355393 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21355403) 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 7 ways as a sum of consecutive naturals, for example, 96085 + ... + 96306.

It is an arithmetic number, because the mean of its divisors is an integer number (3655448).

Almost surely, 2^21355401 is an apocalyptic number.

It is an amenable number.

21355401 is a deficient number, since it is larger than the sum of its proper divisors (7888183).

21355401 is a wasteful number, since it uses less digits than its factorization.

21355401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 192431.

The product of its (nonzero) digits is 600, while the sum is 21.

The square root of 21355401 is about 4621.1904310470. The cubic root of 21355401 is about 277.4401071944.

The spelling of 21355401 in words is "twenty-one million, three hundred fifty-five thousand, four hundred one".