1601220737 has 2 divisors, whose sum is σ = 1601220738. Its totient is φ = 1601220736.

The previous prime is 1601220707. The next prime is 1601220779. The reversal of 1601220737 is 7370221061.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1178136976 + 423083761 = 34324^2 + 20569^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1601220737 is a prime.

It is not a weakly prime, because it can be changed into another prime (1601220707) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 800610368 + 800610369.

It is an arithmetic number, because the mean of its divisors is an integer number (800610369).

Almost surely, 2^1601220737 is an apocalyptic number.

It is an amenable number.

1601220737 is a deficient number, since it is larger than the sum of its proper divisors (1).

1601220737 is an equidigital number, since it uses as much as digits as its factorization.

1601220737 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3528, while the sum is 29.

The square root of 1601220737 is about 40015.2563030652. The cubic root of 1601220737 is about 1169.9044743886.

Adding to 1601220737 its reverse (7370221061), we get a palindrome (8971441798).

The spelling of 1601220737 in words is "one billion, six hundred one million, two hundred twenty thousand, seven hundred thirty-seven".