20956406 has 4 divisors (see below), whose sum is σ = 31434612. Its totient is φ = 10478202.

The previous prime is 20956399. The next prime is 20956423. The reversal of 20956406 is 60465902.

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

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5239100 + ... + 5239103.

It is an arithmetic number, because the mean of its divisors is an integer number (7858653).

Almost surely, 2^20956406 is an apocalyptic number.

20956406 is a deficient number, since it is larger than the sum of its proper divisors (10478206).

20956406 is a wasteful number, since it uses less digits than its factorization.

20956406 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10478205.

The product of its (nonzero) digits is 12960, while the sum is 32.

The square root of 20956406 is about 4577.8167285290. The cubic root of 20956406 is about 275.7013765882.

The spelling of 20956406 in words is "twenty million, nine hundred fifty-six thousand, four hundred six".