21034690 has 16 divisors (see below), whose sum is σ = 38320128. Its totient is φ = 8312176.

The previous prime is 21034687. The next prime is 21034723. The reversal of 21034690 is 9643012.

It is a super-2 number, since 2×21034690² = 884916366792200, which contains 22 as substring.

It is an unprimeable number.

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 in 7 ways as a sum of consecutive naturals, for example, 11842 + ... + 13501.

It is an arithmetic number, because the mean of its divisors is an integer number (2395008).

Almost surely, 2^21034690 is an apocalyptic number.

21034690 is a deficient number, since it is larger than the sum of its proper divisors (17285438).

21034690 is a wasteful number, since it uses less digits than its factorization.

21034690 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25433.

The product of its (nonzero) digits is 1296, while the sum is 25.

The square root of 21034690 is about 4586.3591224412. The cubic root of 21034690 is about 276.0442500640.

The spelling of 21034690 in words is "twenty-one million, thirty-four thousand, six hundred ninety".