1601656501 has 4 divisors (see below), whose sum is σ = 1602006400. Its totient is φ = 1601306604.

The previous prime is 1601656499. The next prime is 1601656519. The reversal of 1601656501 is 1056561061.

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.

It is a cyclic number.

It is not a de Polignac number, because 1601656501 - 2¹ = 1601656499 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1601651501) 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, 167991 + ... + 177268.

It is an arithmetic number, because the mean of its divisors is an integer number (400501600).

Almost surely, 2^1601656501 is an apocalyptic number.

It is an amenable number.

1601656501 is a deficient number, since it is larger than the sum of its proper divisors (349899).

1601656501 is an equidigital number, since it uses as much as digits as its factorization.

1601656501 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 349898.

The product of its (nonzero) digits is 5400, while the sum is 31.

The square root of 1601656501 is about 40020.7009059062. The cubic root of 1601656501 is about 1170.0105925941.

The spelling of 1601656501 in words is "one billion, six hundred one million, six hundred fifty-six thousand, five hundred one".