20815453877674 has 4 divisors (see below), whose sum is σ = 31223180816514. Its totient is φ = 10407726938836.

The previous prime is 20815453877611. The next prime is 20815453877677. The reversal of 20815453877674 is 47677835451802.

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

It can be written as a sum of positive squares in only one way, i.e., 12642184692225 + 8173269185449 = 3555585^2 + 2858893^2 .

It is a Smith number, since the sum of its digits (67) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (20815453877677) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5203863469417 + ... + 5203863469420.

Almost surely, 2^{20815453877674} is an apocalyptic number.

20815453877674 is a deficient number, since it is larger than the sum of its proper divisors (10407726938840).

20815453877674 is a wasteful number, since it uses less digits than its factorization.

20815453877674 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10407726938839.

The product of its (nonzero) digits is 316108800, while the sum is 67.

The spelling of 20815453877674 in words is "twenty trillion, eight hundred fifteen billion, four hundred fifty-three million, eight hundred seventy-seven thousand, six hundred seventy-four".