1661054653 has 4 divisors (see below), whose sum is σ = 1705948060. Its totient is φ = 1616161248.

The previous prime is 1661054627. The next prime is 1661054657. The reversal of 1661054653 is 3564501661.

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 1577916729 + 83137924 = 39723^2 + 9118^2 .

It is a cyclic number.

It is not a de Polignac number, because 1661054653 - 2²⁵ = 1627500221 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (37), and also a Moran number because the ratio is a prime number: 44893369 = 1661054653 / (1 + 6 + 6 + 1 + 0 + 5 + 4 + 6 + 5 + 3).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1661054657) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 22446648 + ... + 22446721.

It is an arithmetic number, because the mean of its divisors is an integer number (426487015).

Almost surely, 2^1661054653 is an apocalyptic number.

It is an amenable number.

1661054653 is a deficient number, since it is larger than the sum of its proper divisors (44893407).

1661054653 is an equidigital number, since it uses as much as digits as its factorization.

1661054653 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44893406.

The product of its (nonzero) digits is 64800, while the sum is 37.

The square root of 1661054653 is about 40756.0382397504. The cubic root of 1661054653 is about 1184.2988494635.

The spelling of 1661054653 in words is "one billion, six hundred sixty-one million, fifty-four thousand, six hundred fifty-three".