20667406 has 4 divisors (see below), whose sum is σ = 31001112. Its totient is φ = 10333702.

The previous prime is 20667397. The next prime is 20667433. The reversal of 20667406 is 60476602.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 60476602 = 2 ⋅30238301.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5166850 + ... + 5166853.

It is an arithmetic number, because the mean of its divisors is an integer number (7750278).

Almost surely, 2^20667406 is an apocalyptic number.

20667406 is a deficient number, since it is larger than the sum of its proper divisors (10333706).

20667406 is a wasteful number, since it uses less digits than its factorization.

20667406 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10333705.

The product of its (nonzero) digits is 12096, while the sum is 31.

The square root of 20667406 is about 4546.1418807600. The cubic root of 20667406 is about 274.4281494268.

The spelling of 20667406 in words is "twenty million, six hundred sixty-seven thousand, four hundred six".