1661189141 has 8 divisors (see below), whose sum is σ = 1688199744. Its totient is φ = 1634345280.

The previous prime is 1661189137. The next prime is 1661189161. The reversal of 1661189141 is 1419811661.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1661189141 - 2² = 1661189137 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1661189095 and 1661189104.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1661189161) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21521 + ... + 61526.

It is an arithmetic number, because the mean of its divisors is an integer number (211024968).

Almost surely, 2^1661189141 is an apocalyptic number.

It is an amenable number.

1661189141 is a deficient number, since it is larger than the sum of its proper divisors (27010603).

1661189141 is an equidigital number, since it uses as much as digits as its factorization.

1661189141 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83371.

The product of its digits is 10368, while the sum is 38.

The square root of 1661189141 is about 40757.6881213839. The cubic root of 1661189141 is about 1184.3308110218.

The spelling of 1661189141 in words is "one billion, six hundred sixty-one million, one hundred eighty-nine thousand, one hundred forty-one".