1601654581 has 4 divisors (see below), whose sum is σ = 1601736192. Its totient is φ = 1601572972.

The previous prime is 1601654563. The next prime is 1601654599. The reversal of 1601654581 is 1854561061.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is an interprime number because it is at equal distance from previous prime (1601654563) and next prime (1601654599).

It is a cyclic number.

It is not a de Polignac number, because 1601654581 - 2²⁷ = 1467436853 is a prime.

It is a super-2 number, since 2×1601654581² = 5130594793676571122, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1601654581.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1601654981) 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, 8460 + ... + 57226.

It is an arithmetic number, because the mean of its divisors is an integer number (400434048).

Almost surely, 2^1601654581 is an apocalyptic number.

It is an amenable number.

1601654581 is a deficient number, since it is larger than the sum of its proper divisors (81611).

1601654581 is an equidigital number, since it uses as much as digits as its factorization.

1601654581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 81610.

The product of its (nonzero) digits is 28800, while the sum is 37.

The square root of 1601654581 is about 40020.6769183131. The cubic root of 1601654581 is about 1170.0101250737.

The spelling of 1601654581 in words is "one billion, six hundred one million, six hundred fifty-four thousand, five hundred eighty-one".