20172256601949 has 16 divisors (see below), whose sum is σ = 30692522559040. Its totient is φ = 13084706984400.

The previous prime is 20172256601927. The next prime is 20172256601971. The reversal of 20172256601949 is 94910665227102.

It is a happy number.

20172256601949 is a `hidden beast` number, since 2 + 0 + 1 + 7 + 2 + 25 + 6 + 601 + 9 + 4 + 9 = 666.

It is an interprime number because it is at equal distance from previous prime (20172256601927) and next prime (20172256601971).

It is not a de Polignac number, because 20172256601949 - 2¹⁶ = 20172256536413 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20172256601895 and 20172256601904.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20172256600949) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10096223527 + ... + 10096225524.

It is an arithmetic number, because the mean of its divisors is an integer number (1918282659940).

Almost surely, 2^{20172256601949} is an apocalyptic number.

It is an amenable number.

20172256601949 is a deficient number, since it is larger than the sum of its proper divisors (10520265957091).

20172256601949 is a wasteful number, since it uses less digits than its factorization.

20172256601949 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20192449097 (or 20192449091 counting only the distinct ones).

The product of its (nonzero) digits is 3265920, while the sum is 54.

The spelling of 20172256601949 in words is "twenty trillion, one hundred seventy-two billion, two hundred fifty-six million, six hundred one thousand, nine hundred forty-nine".