1661140516 has 48 divisors (see below), whose sum is σ = 3577392000. Its totient is φ = 658672128.

The previous prime is 1661140513. The next prime is 1661140519. The reversal of 1661140516 is 6150411661.

It is an interprime number because it is at equal distance from previous prime (1661140513) and next prime (1661140519).

It is not an unprimeable number, because it can be changed into a prime (1661140511) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1491 + ... + 57658.

It is an arithmetic number, because the mean of its divisors is an integer number (74529000).

Almost surely, 2^1661140516 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1661140516, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1788696000).

1661140516 is an abundant number, since it is smaller than the sum of its proper divisors (1916251484).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1661140516 is a wasteful number, since it uses less digits than its factorization.

1661140516 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 59236 (or 59234 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 31.

The square root of 1661140516 is about 40757.0916037933. The cubic root of 1661140516 is about 1184.3192553143.

The spelling of 1661140516 in words is "one billion, six hundred sixty-one million, one hundred forty thousand, five hundred sixteen".