21147101 has 4 divisors (see below), whose sum is σ = 21172092. Its totient is φ = 21122112.

The previous prime is 21147083. The next prime is 21147107. The reversal of 21147101 is 10174112.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 16080100 + 5067001 = 4010^2 + 2251^2 .

It is a cyclic number.

It is not a de Polignac number, because 21147101 - 2⁶ = 21147037 is a prime.

It is a super-3 number, since 3×21147101³ (a number of 23 digits) contains 333 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21147101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21147107) 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, 11180 + ... + 12933.

It is an arithmetic number, because the mean of its divisors is an integer number (5293023).

Almost surely, 2^21147101 is an apocalyptic number.

It is an amenable number.

21147101 is a deficient number, since it is larger than the sum of its proper divisors (24991).

21147101 is an equidigital number, since it uses as much as digits as its factorization.

21147101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24990.

The product of its (nonzero) digits is 56, while the sum is 17.

The square root of 21147101 is about 4598.5977210450. The cubic root of 21147101 is about 276.5351105969.

The spelling of 21147101 in words is "twenty-one million, one hundred forty-seven thousand, one hundred one".