1780138749 has 16 divisors (see below), whose sum is σ = 2383142400. Its totient is φ = 1181958960.

The previous prime is 1780138739. The next prime is 1780138793. The reversal of 1780138749 is 9478310871.

It is not a de Polignac number, because 1780138749 - 2⁷ = 1780138621 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1780138698 and 1780138707.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1780138739) 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 15 ways as a sum of consecutive naturals, for example, 982054 + ... + 983864.

It is an arithmetic number, because the mean of its divisors is an integer number (148946400).

Almost surely, 2^1780138749 is an apocalyptic number.

It is an amenable number.

1780138749 is a deficient number, since it is larger than the sum of its proper divisors (603003651).

1780138749 is a wasteful number, since it uses less digits than its factorization.

1780138749 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2960.

The product of its (nonzero) digits is 338688, while the sum is 48.

The square root of 1780138749 is about 42191.6905207649. The cubic root of 1780138749 is about 1211.9497625105.

The spelling of 1780138749 in words is "one billion, seven hundred eighty million, one hundred thirty-eight thousand, seven hundred forty-nine".