1642641377 has 4 divisors (see below), whose sum is σ = 1768998420. Its totient is φ = 1516284336.

The previous prime is 1642641373. The next prime is 1642641389. The reversal of 1642641377 is 7731462461.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7731462461 = 61543 ⋅125627.

It can be written as a sum of positive squares in 2 ways, for example, as 806332816 + 836308561 = 28396^2 + 28919^2 .

It is a cyclic number.

It is not a de Polignac number, because 1642641377 - 2² = 1642641373 is a prime.

It is a super-2 number, since 2×1642641377² = 5396541386864912258, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1642641373) 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 in 3 ways as a sum of consecutive naturals, for example, 63178502 + ... + 63178527.

It is an arithmetic number, because the mean of its divisors is an integer number (442249605).

Almost surely, 2^1642641377 is an apocalyptic number.

It is an amenable number.

1642641377 is a deficient number, since it is larger than the sum of its proper divisors (126357043).

1642641377 is a wasteful number, since it uses less digits than its factorization.

1642641377 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 126357042.

The product of its digits is 169344, while the sum is 41.

The square root of 1642641377 is about 40529.5124199638. The cubic root of 1642641377 is about 1179.9064794694.

The spelling of 1642641377 in words is "one billion, six hundred forty-two million, six hundred forty-one thousand, three hundred seventy-seven".