1358961881 has 4 divisors (see below), whose sum is σ = 1359035700. Its totient is φ = 1358888064.

The previous prime is 1358961823. The next prime is 1358961889. The reversal of 1358961881 is 1881698531.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 520569856 + 838392025 = 22816^2 + 28955^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1358961881 is a prime.

It is a super-2 number, since 2×1358961881² = 3693554788022116322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1358961889) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15725 + ... + 54453.

It is an arithmetic number, because the mean of its divisors is an integer number (339758925).

Almost surely, 2^1358961881 is an apocalyptic number.

It is an amenable number.

1358961881 is a deficient number, since it is larger than the sum of its proper divisors (73819).

1358961881 is an equidigital number, since it uses as much as digits as its factorization.

1358961881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73818.

The product of its digits is 414720, while the sum is 50.

The square root of 1358961881 is about 36864.1001653370. The cubic root of 1358961881 is about 1107.6496764315.

The spelling of 1358961881 in words is "one billion, three hundred fifty-eight million, nine hundred sixty-one thousand, eight hundred eighty-one".