20193979 has 18 divisors (see below), whose sum is σ = 23148036. Its totient is φ = 17606160.

The previous prime is 20193967. The next prime is 20193991. The reversal of 20193979 is 97939102.

It is an interprime number because it is at equal distance from previous prime (20193967) and next prime (20193991).

It is not a de Polignac number, because 20193979 - 2¹¹ = 20191931 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20193949) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 60844 + ... + 61174.

It is an arithmetic number, because the mean of its divisors is an integer number (1286002).

Almost surely, 2^20193979 is an apocalyptic number.

20193979 is a deficient number, since it is larger than the sum of its proper divisors (2954057).

20193979 is a wasteful number, since it uses less digits than its factorization.

20193979 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 395 (or 363 counting only the distinct ones).

The product of its (nonzero) digits is 30618, while the sum is 40.

The square root of 20193979 is about 4493.7711334691. The cubic root of 20193979 is about 272.3165063817.

The spelling of 20193979 in words is "twenty million, one hundred ninety-three thousand, nine hundred seventy-nine".