1620739723579 has 2 divisors, whose sum is σ = 1620739723580. Its totient is φ = 1620739723578.

The previous prime is 1620739723573. The next prime is 1620739723591. The reversal of 1620739723579 is 9753279370261.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1620739723579 - 2³³ = 1612149788987 is a prime.

It is not a weakly prime, because it can be changed into another prime (1620739723573) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 810369861789 + 810369861790.

It is an arithmetic number, because the mean of its divisors is an integer number (810369861790).

Almost surely, 2^{1620739723579} is an apocalyptic number.

1620739723579 is a deficient number, since it is larger than the sum of its proper divisors (1).

1620739723579 is an equidigital number, since it uses as much as digits as its factorization.

1620739723579 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 30005640, while the sum is 61.

The spelling of 1620739723579 in words is "one trillion, six hundred twenty billion, seven hundred thirty-nine million, seven hundred twenty-three thousand, five hundred seventy-nine".