1661140533 has 32 divisors (see below), whose sum is σ = 2528983296. Its totient is φ = 960795648.

The previous prime is 1661140519. The next prime is 1661140553. The reversal of 1661140533 is 3350411661.

It is not a de Polignac number, because 1661140533 - 2¹² = 1661136437 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1661140533.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1661140513) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 703591 + ... + 705947.

It is an arithmetic number, because the mean of its divisors is an integer number (79030728).

Almost surely, 2^1661140533 is an apocalyptic number.

1661140533 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

It is an amenable number.

1661140533 is a deficient number, since it is larger than the sum of its proper divisors (867842763).

1661140533 is a wasteful number, since it uses less digits than its factorization.

1661140533 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3453.

The product of its (nonzero) digits is 6480, while the sum is 30.

The square root of 1661140533 is about 40757.0918123460. The cubic root of 1661140533 is about 1184.3192593544.

The spelling of 1661140533 in words is "one billion, six hundred sixty-one million, one hundred forty thousand, five hundred thirty-three".