36784921661 has 2 divisors, whose sum is σ = 36784921662. Its totient is φ = 36784921660.

The previous prime is 36784921631. The next prime is 36784921669. The reversal of 36784921661 is 16612948763.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 30497383225 + 6287538436 = 174635^2 + 79294^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-36784921661 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (36784921669) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 18392460830 + 18392460831.

It is an arithmetic number, because the mean of its divisors is an integer number (18392460831).

Almost surely, 2^36784921661 is an apocalyptic number.

It is an amenable number.

36784921661 is a deficient number, since it is larger than the sum of its proper divisors (1).

36784921661 is an equidigital number, since it uses as much as digits as its factorization.

36784921661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2612736, while the sum is 53.

The spelling of 36784921661 in words is "thirty-six billion, seven hundred eighty-four million, nine hundred twenty-one thousand, six hundred sixty-one".