1395621109 has 2 divisors, whose sum is σ = 1395621110. Its totient is φ = 1395621108.

The previous prime is 1395621107. The next prime is 1395621151. The reversal of 1395621109 is 9011265931.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 968578884 + 427042225 = 31122^2 + 20665^2 .

It is a cyclic number.

It is not a de Polignac number, because 1395621109 - 2¹ = 1395621107 is a prime.

Together with 1395621107, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1395621107) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 697810554 + 697810555.

It is an arithmetic number, because the mean of its divisors is an integer number (697810555).

Almost surely, 2^1395621109 is an apocalyptic number.

It is an amenable number.

1395621109 is a deficient number, since it is larger than the sum of its proper divisors (1).

1395621109 is an equidigital number, since it uses as much as digits as its factorization.

1395621109 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 14580, while the sum is 37.

The square root of 1395621109 is about 37358.0126478912. The cubic root of 1395621109 is about 1117.5213865819.

The spelling of 1395621109 in words is "one billion, three hundred ninety-five million, six hundred twenty-one thousand, one hundred nine".