1398695638 has 16 divisors (see below), whose sum is σ = 2222265024. Its totient is φ = 657970560.

The previous prime is 1398695633. The next prime is 1398695647. The reversal of 1398695638 is 8365968931.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1398695633) 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, 118003 + ... + 129313.

It is an arithmetic number, because the mean of its divisors is an integer number (138891564).

Almost surely, 2^1398695638 is an apocalyptic number.

1398695638 is a deficient number, since it is larger than the sum of its proper divisors (823569386).

1398695638 is a wasteful number, since it uses less digits than its factorization.

1398695638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14967.

The product of its digits is 8398080, while the sum is 58.

The square root of 1398695638 is about 37399.1395355562. The cubic root of 1398695638 is about 1118.3414114277.

The spelling of 1398695638 in words is "one billion, three hundred ninety-eight million, six hundred ninety-five thousand, six hundred thirty-eight".