1918153709 has 2 divisors, whose sum is σ = 1918153710. Its totient is φ = 1918153708.

The previous prime is 1918153691. The next prime is 1918153739. The reversal of 1918153709 is 9073518191.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1876189225 + 41964484 = 43315^2 + 6478^2 .

It is a cyclic number.

It is not a de Polignac number, because 1918153709 - 2¹² = 1918149613 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1918153709.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1918153739) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 959076854 + 959076855.

It is an arithmetic number, because the mean of its divisors is an integer number (959076855).

Almost surely, 2^1918153709 is an apocalyptic number.

It is an amenable number.

1918153709 is a deficient number, since it is larger than the sum of its proper divisors (1).

1918153709 is an equidigital number, since it uses as much as digits as its factorization.

1918153709 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 68040, while the sum is 44.

The square root of 1918153709 is about 43796.7317159626. The cubic root of 1918153709 is about 1242.4944818770.

The spelling of 1918153709 in words is "one billion, nine hundred eighteen million, one hundred fifty-three thousand, seven hundred nine".