21670354 has 8 divisors (see below), whose sum is σ = 32525820. Its totient is φ = 10828416.

The previous prime is 21670339. The next prime is 21670373. The reversal of 21670354 is 45307612.

It can be written as a sum of positive squares in 2 ways, for example, as 19158129 + 2512225 = 4377^2 + 1585^2 .

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

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3142 + ... + 7294.

Almost surely, 2^21670354 is an apocalyptic number.

21670354 is a deficient number, since it is larger than the sum of its proper divisors (10855466).

21670354 is a wasteful number, since it uses less digits than its factorization.

21670354 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6764.

The product of its (nonzero) digits is 5040, while the sum is 28.

The square root of 21670354 is about 4655.1427475428. The cubic root of 21670354 is about 278.7973674591.

Adding to 21670354 its reverse (45307612), we get a palindrome (66977966).

The spelling of 21670354 in words is "twenty-one million, six hundred seventy thousand, three hundred fifty-four".