1388640202 has 4 divisors (see below), whose sum is σ = 2082960306. Its totient is φ = 694320100.

The previous prime is 1388640103. The next prime is 1388640233. The reversal of 1388640202 is 2020468831.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 2020468831 = 29 ⋅69671339.

It can be written as a sum of positive squares in only one way, i.e., 1357848801 + 30791401 = 36849^2 + 5549^2 .

It is a super-2 number, since 2×1388640202² = 3856643221221201608, which contains 22 as substring.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 347160049 + ... + 347160052.

Almost surely, 2^1388640202 is an apocalyptic number.

1388640202 is a deficient number, since it is larger than the sum of its proper divisors (694320104).

1388640202 is an equidigital number, since it uses as much as digits as its factorization.

1388640202 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 694320103.

The product of its (nonzero) digits is 18432, while the sum is 34.

The square root of 1388640202 is about 37264.4629908979. The cubic root of 1388640202 is about 1115.6549878163.

The spelling of 1388640202 in words is "one billion, three hundred eighty-eight million, six hundred forty thousand, two hundred two".