1653409891 has 8 divisors (see below), whose sum is σ = 1928175200. Its totient is φ = 1417208184.

The previous prime is 1653409859. The next prime is 1653409907. The reversal of 1653409891 is 1989043561.

It is not a de Polignac number, because 1653409891 - 2⁵ = 1653409859 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1653409801) 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, 2409876 + ... + 2410561.

It is an arithmetic number, because the mean of its divisors is an integer number (241021900).

Almost surely, 2^1653409891 is an apocalyptic number.

1653409891 is a deficient number, since it is larger than the sum of its proper divisors (274765309).

1653409891 is an frugal number, since it uses more digits than its factorization.

1653409891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4820458 (or 4820444 counting only the distinct ones).

The product of its (nonzero) digits is 233280, while the sum is 46.

The square root of 1653409891 is about 40662.1432170022. The cubic root of 1653409891 is about 1182.4792007510.

The spelling of 1653409891 in words is "one billion, six hundred fifty-three million, four hundred nine thousand, eight hundred ninety-one".