31445644388 has 6 divisors (see below), whose sum is σ = 55029877686. Its totient is φ = 15722822192.

The previous prime is 31445644381. The next prime is 31445644393. The reversal of 31445644388 is 88344654413.

It can be written as a sum of positive squares in only one way, i.e., 21910512484 + 9535131904 = 148022^2 + 97648^2 .

It is not an unprimeable number, because it can be changed into a prime (31445644381) 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 as a sum of consecutive naturals, namely, 3930705545 + ... + 3930705552.

It is an arithmetic number, because the mean of its divisors is an integer number (9171646281).

Almost surely, 2^31445644388 is an apocalyptic number.

It is an amenable number.

31445644388 is a deficient number, since it is larger than the sum of its proper divisors (23584233298).

31445644388 is a wasteful number, since it uses less digits than its factorization.

31445644388 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7861411101 (or 7861411099 counting only the distinct ones).

The product of its digits is 4423680, while the sum is 50.

The spelling of 31445644388 in words is "thirty-one billion, four hundred forty-five million, six hundred forty-four thousand, three hundred eighty-eight".