172804020947 has 4 divisors (see below), whose sum is σ = 178762780320. Its totient is φ = 166845261576.

The previous prime is 172804020943. The next prime is 172804020971. The reversal of 172804020947 is 749020408271.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 749020408271 = 42157 ⋅17767403.

It is a cyclic number.

It is not a de Polignac number, because 172804020947 - 2² = 172804020943 is a prime.

It is a super-2 number, since 2×172804020947² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 172804020898 and 172804020907.

It is not an unprimeable number, because it can be changed into a prime (172804020943) 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, 2979379643 + ... + 2979379700.

It is an arithmetic number, because the mean of its divisors is an integer number (44690695080).

Almost surely, 2^172804020947 is an apocalyptic number.

172804020947 is a deficient number, since it is larger than the sum of its proper divisors (5958759373).

172804020947 is an equidigital number, since it uses as much as digits as its factorization.

172804020947 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5958759372.

The product of its (nonzero) digits is 225792, while the sum is 44.

The spelling of 172804020947 in words is "one hundred seventy-two billion, eight hundred four million, twenty thousand, nine hundred forty-seven".