21612070 has 16 divisors (see below), whose sum is σ = 39953808. Its totient is φ = 8411040.

The previous prime is 21612067. The next prime is 21612077. The reversal of 21612070 is 7021612.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21612077) 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 in 7 ways as a sum of consecutive naturals, for example, 28836 + ... + 29575.

It is an arithmetic number, because the mean of its divisors is an integer number (2497113).

Almost surely, 2^21612070 is an apocalyptic number.

21612070 is a deficient number, since it is larger than the sum of its proper divisors (18341738).

21612070 is a wasteful number, since it uses less digits than its factorization.

21612070 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 58455.

The product of its (nonzero) digits is 168, while the sum is 19.

The square root of 21612070 is about 4648.8783593465. The cubic root of 21612070 is about 278.5471944104.

Adding to 21612070 its reverse (7021612), we get a palindrome (28633682).

The spelling of 21612070 in words is "twenty-one million, six hundred twelve thousand, seventy".