1601135881 has 2 divisors, whose sum is σ = 1601135882. Its totient is φ = 1601135880.

The previous prime is 1601135761. The next prime is 1601135929. The reversal of 1601135881 is 1885311061.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1452295881 + 148840000 = 38109^2 + 12200^2 .

It is a cyclic number.

It is not a de Polignac number, because 1601135881 - 2⁹ = 1601135369 is a prime.

It is a super-2 number, since 2×1601135881² = 5127272218851292322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1601132881) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 800567940 + 800567941.

It is an arithmetic number, because the mean of its divisors is an integer number (800567941).

Almost surely, 2^1601135881 is an apocalyptic number.

It is an amenable number.

1601135881 is a deficient number, since it is larger than the sum of its proper divisors (1).

1601135881 is an equidigital number, since it uses as much as digits as its factorization.

1601135881 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5760, while the sum is 34.

The square root of 1601135881 is about 40014.1959934221. The cubic root of 1601135881 is about 1169.8838078297.

The spelling of 1601135881 in words is "one billion, six hundred one million, one hundred thirty-five thousand, eight hundred eighty-one".