1640442440461 has 12 divisors (see below), whose sum is σ = 1820983742172. Its totient is φ = 1476545840000.

The previous prime is 1640442440411. The next prime is 1640442440467.

1640442440461 is nontrivially palindromic in base 10.

It can be written as a sum of positive squares in 2 ways, for example, as 1045066621225 + 595375819236 = 1022285^2 + 771606^2 .

It is not a de Polignac number, because 1640442440461 - 2²³ = 1640434051853 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1640442440467) 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, 67103500 + ... + 67127941.

It is an arithmetic number, because the mean of its divisors is an integer number (151748645181).

Almost surely, 2^{1640442440461} is an apocalyptic number.

1640442440461 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1640442440461 is a deficient number, since it is larger than the sum of its proper divisors (180541301711).

1640442440461 is a wasteful number, since it uses less digits than its factorization.

1640442440461 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 134231564 (or 134231553 counting only the distinct ones).

The product of its (nonzero) digits is 294912, while the sum is 40.

The spelling of 1640442440461 in words is "one trillion, six hundred forty billion, four hundred forty-two million, four hundred forty thousand, four hundred sixty-one".