1031243378661 has 12 divisors (see below), whose sum is σ = 1490426438592. Its totient is φ = 687102046056.

The previous prime is 1031243378657. The next prime is 1031243378741. The reversal of 1031243378661 is 1668733421301.

1031243378661 is a `hidden beast` number, since 1 + 0 + 31 + 243 + 378 + 6 + 6 + 1 = 666.

It is not a de Polignac number, because 1031243378661 - 2² = 1031243378657 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1031243378861) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 32778381 + ... + 32809826.

It is an arithmetic number, because the mean of its divisors is an integer number (124202203216).

Almost surely, 2^{1031243378661} is an apocalyptic number.

It is an amenable number.

1031243378661 is a deficient number, since it is larger than the sum of its proper divisors (459183059931).

1031243378661 is a wasteful number, since it uses less digits than its factorization.

1031243378661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65589960 (or 65589957 counting only the distinct ones).

The product of its (nonzero) digits is 435456, while the sum is 45.

Adding to 1031243378661 its reverse (1668733421301), we get a palindrome (2699976799962).

The spelling of 1031243378661 in words is "one trillion, thirty-one billion, two hundred forty-three million, three hundred seventy-eight thousand, six hundred sixty-one".