20394779 has 4 divisors (see below), whose sum is σ = 20543784. Its totient is φ = 20245776.

The previous prime is 20394769. The next prime is 20394793. The reversal of 20394779 is 97749302.

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

It is a cyclic number.

It is not a de Polignac number, because 20394779 - 2⁸ = 20394523 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20394709) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 74297 + ... + 74570.

It is an arithmetic number, because the mean of its divisors is an integer number (5135946).

Almost surely, 2^20394779 is an apocalyptic number.

20394779 is a deficient number, since it is larger than the sum of its proper divisors (149005).

20394779 is a wasteful number, since it uses less digits than its factorization.

20394779 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 149004.

The product of its (nonzero) digits is 95256, while the sum is 41.

The square root of 20394779 is about 4516.0579048546. The cubic root of 20394779 is about 273.2161294388.

The spelling of 20394779 in words is "twenty million, three hundred ninety-four thousand, seven hundred seventy-nine".