1355780123578 has 4 divisors (see below), whose sum is σ = 2033670185370. Its totient is φ = 677890061788.

The previous prime is 1355780123573. The next prime is 1355780123603. The reversal of 1355780123578 is 8753210875531.

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., 789046688089 + 566733435489 = 888283^2 + 752817^2 .

It is not an unprimeable number, because it can be changed into a prime (1355780123573) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 338945030893 + ... + 338945030896.

Almost surely, 2^{1355780123578} is an apocalyptic number.

1355780123578 is a deficient number, since it is larger than the sum of its proper divisors (677890061792).

1355780123578 is an equidigital number, since it uses as much as digits as its factorization.

1355780123578 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 677890061791.

The product of its (nonzero) digits is 7056000, while the sum is 55.

The spelling of 1355780123578 in words is "one trillion, three hundred fifty-five billion, seven hundred eighty million, one hundred twenty-three thousand, five hundred seventy-eight".