1778890641 has 8 divisors (see below), whose sum is σ = 2587477344. Its totient is φ = 1078115520.

The previous prime is 1778890621. The next prime is 1778890643. The reversal of 1778890641 is 1460988771.

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

It is not a de Polignac number, because 1778890641 - 2⁹ = 1778890129 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1778890643) 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, 26952856 + ... + 26952921.

It is an arithmetic number, because the mean of its divisors is an integer number (323434668).

Almost surely, 2^1778890641 is an apocalyptic number.

1778890641 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1778890641 is a deficient number, since it is larger than the sum of its proper divisors (808586703).

1778890641 is a wasteful number, since it uses less digits than its factorization.

1778890641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53905791.

The product of its (nonzero) digits is 677376, while the sum is 51.

The square root of 1778890641 is about 42176.8970053512. The cubic root of 1778890641 is about 1211.6664516632. Note that the first 3 decimals are identical.

The spelling of 1778890641 in words is "one billion, seven hundred seventy-eight million, eight hundred ninety thousand, six hundred forty-one".