378728621549 has 2 divisors, whose sum is σ = 378728621550. Its totient is φ = 378728621548.

The previous prime is 378728621533. The next prime is 378728621639. The reversal of 378728621549 is 945126827873.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 307228535524 + 71500086025 = 554282^2 + 267395^2 .

It is a cyclic number.

It is not a de Polignac number, because 378728621549 - 2⁴ = 378728621533 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 378728621491 and 378728621500.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (378728623549) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 189364310774 + 189364310775.

It is an arithmetic number, because the mean of its divisors is an integer number (189364310775).

Almost surely, 2^378728621549 is an apocalyptic number.

It is an amenable number.

378728621549 is a deficient number, since it is larger than the sum of its proper divisors (1).

378728621549 is an equidigital number, since it uses as much as digits as its factorization.

378728621549 is an evil number, because the sum of its binary digits is even.

The product of its digits is 40642560, while the sum is 62.

The spelling of 378728621549 in words is "three hundred seventy-eight billion, seven hundred twenty-eight million, six hundred twenty-one thousand, five hundred forty-nine".