1664127739 has 8 divisors (see below), whose sum is σ = 1762373808. Its totient is φ = 1565921280.

The previous prime is 1664127719. The next prime is 1664127757. The reversal of 1664127739 is 9377214661.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1664127739 - 2¹³ = 1664119547 is a prime.

It is a super-2 number, since 2×1664127739² = 5538642263418504242, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1664127719) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 162604 + ... + 172534.

It is an arithmetic number, because the mean of its divisors is an integer number (220296726).

Almost surely, 2^1664127739 is an apocalyptic number.

1664127739 is a deficient number, since it is larger than the sum of its proper divisors (98246069).

1664127739 is an equidigital number, since it uses as much as digits as its factorization.

1664127739 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19805.

The product of its digits is 381024, while the sum is 46.

The square root of 1664127739 is about 40793.7218086313. The cubic root of 1664127739 is about 1185.0287492061.

The spelling of 1664127739 in words is "one billion, six hundred sixty-four million, one hundred twenty-seven thousand, seven hundred thirty-nine".