21770894 has 4 divisors (see below), whose sum is σ = 32656344. Its totient is φ = 10885446.

The previous prime is 21770893. The next prime is 21770927. The reversal of 21770894 is 49807712.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21770893) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5442722 + ... + 5442725.

It is an arithmetic number, because the mean of its divisors is an integer number (8164086).

Almost surely, 2^21770894 is an apocalyptic number.

21770894 is a deficient number, since it is larger than the sum of its proper divisors (10885450).

21770894 is a wasteful number, since it uses less digits than its factorization.

21770894 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10885449.

The product of its (nonzero) digits is 28224, while the sum is 38.

The square root of 21770894 is about 4665.9290607552. The cubic root of 21770894 is about 279.2278641906.

The spelling of 21770894 in words is "twenty-one million, seven hundred seventy thousand, eight hundred ninety-four".