161459201861 has 4 divisors (see below), whose sum is σ = 161643306732. Its totient is φ = 161275096992.

The previous prime is 161459201843. The next prime is 161459201899. The reversal of 161459201861 is 168102954161.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 85012481761 + 76446720100 = 291569^2 + 276490^2 .

It is a cyclic number.

It is not a de Polignac number, because 161459201861 - 2⁶ = 161459201797 is a prime.

It is a super-2 number, since 2×161459201861² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161459204861) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 92051120 + ... + 92052873.

It is an arithmetic number, because the mean of its divisors is an integer number (40410826683).

Almost surely, 2^161459201861 is an apocalyptic number.

It is an amenable number.

161459201861 is a deficient number, since it is larger than the sum of its proper divisors (184104871).

161459201861 is an equidigital number, since it uses as much as digits as its factorization.

161459201861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 184104870.

The product of its (nonzero) digits is 103680, while the sum is 44.

The spelling of 161459201861 in words is "one hundred sixty-one billion, four hundred fifty-nine million, two hundred one thousand, eight hundred sixty-one".