1540043778657 has 16 divisors (see below), whose sum is σ = 2142748016640. Its totient is φ = 982020963792.

The previous prime is 1540043778631. The next prime is 1540043778659. The reversal of 1540043778657 is 7568773400451.

It is not a de Polignac number, because 1540043778657 - 2⁶ = 1540043778593 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1540043778597 and 1540043778606.

It is not an unprimeable number, because it can be changed into a prime (1540043778659) 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, 1558944 + ... + 2347422.

It is an arithmetic number, because the mean of its divisors is an integer number (133921751040).

Almost surely, 2^{1540043778657} is an apocalyptic number.

It is an amenable number.

1540043778657 is a deficient number, since it is larger than the sum of its proper divisors (602704237983).

1540043778657 is a wasteful number, since it uses less digits than its factorization.

1540043778657 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 816812.

The product of its (nonzero) digits is 19756800, while the sum is 57.

The spelling of 1540043778657 in words is "one trillion, five hundred forty billion, forty-three million, seven hundred seventy-eight thousand, six hundred fifty-seven".