1815793137253 has 4 divisors (see below), whose sum is σ = 1878406693740. Its totient is φ = 1753179580768.

The previous prime is 1815793137247. The next prime is 1815793137287. The reversal of 1815793137253 is 3527313975181.

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

It can be written as a sum of positive squares in 2 ways, for example, as 1150593039649 + 665200097604 = 1072657^2 + 815598^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1815793137253 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1815793137194 and 1815793137203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1815793137233) 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, 31306778200 + ... + 31306778257.

It is an arithmetic number, because the mean of its divisors is an integer number (469601673435).

Almost surely, 2^{1815793137253} is an apocalyptic number.

It is an amenable number.

1815793137253 is a deficient number, since it is larger than the sum of its proper divisors (62613556487).

1815793137253 is an equidigital number, since it uses as much as digits as its factorization.

1815793137253 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 62613556486.

The product of its digits is 4762800, while the sum is 55.

The spelling of 1815793137253 in words is "one trillion, eight hundred fifteen billion, seven hundred ninety-three million, one hundred thirty-seven thousand, two hundred fifty-three".