1537813661 has 2 divisors, whose sum is σ = 1537813662. Its totient is φ = 1537813660.

The previous prime is 1537813657. The next prime is 1537813729. The reversal of 1537813661 is 1663187351.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1430276761 + 107536900 = 37819^2 + 10370^2 .

It is a cyclic number.

It is not a de Polignac number, because 1537813661 - 2² = 1537813657 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1537813631) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 768906830 + 768906831.

It is an arithmetic number, because the mean of its divisors is an integer number (768906831).

Almost surely, 2^1537813661 is an apocalyptic number.

It is an amenable number.

1537813661 is a deficient number, since it is larger than the sum of its proper divisors (1).

1537813661 is an equidigital number, since it uses as much as digits as its factorization.

1537813661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 90720, while the sum is 41.

The square root of 1537813661 is about 39214.9673084143. The cubic root of 1537813661 is about 1154.2536012008.

The spelling of 1537813661 in words is "one billion, five hundred thirty-seven million, eight hundred thirteen thousand, six hundred sixty-one".