21700361 has 4 divisors (see below), whose sum is σ = 21844224. Its totient is φ = 21556500.

The previous prime is 21700351. The next prime is 21700379. The reversal of 21700361 is 16300712.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21700361 - 2⁶ = 21700297 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21700321) 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, 71705 + ... + 72006.

It is an arithmetic number, because the mean of its divisors is an integer number (5461056).

Almost surely, 2^21700361 is an apocalyptic number.

It is an amenable number.

21700361 is a deficient number, since it is larger than the sum of its proper divisors (143863).

21700361 is a wasteful number, since it uses less digits than its factorization.

21700361 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 143862.

The product of its (nonzero) digits is 252, while the sum is 20.

The square root of 21700361 is about 4658.3646272056. The cubic root of 21700361 is about 278.9259919408.

The spelling of 21700361 in words is "twenty-one million, seven hundred thousand, three hundred sixty-one".