10001011091861 has 2 divisors, whose sum is σ = 10001011091862. Its totient is φ = 10001011091860.

The previous prime is 10001011091843. The next prime is 10001011091933. The reversal of 10001011091861 is 16819011010001.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 9669574844836 + 331436247025 = 3109594^2 + 575705^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-10001011091861 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (10001011091801) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5000505545930 + 5000505545931.

It is an arithmetic number, because the mean of its divisors is an integer number (5000505545931).

Almost surely, 2^{10001011091861} is an apocalyptic number.

It is an amenable number.

10001011091861 is a deficient number, since it is larger than the sum of its proper divisors (1).

10001011091861 is an equidigital number, since it uses as much as digits as its factorization.

10001011091861 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 432, while the sum is 29.

The spelling of 10001011091861 in words is "ten trillion, one billion, eleven million, ninety-one thousand, eight hundred sixty-one".