31621207073 has 4 divisors (see below), whose sum is σ = 32392456068. Its totient is φ = 30849958080.

The previous prime is 31621207069. The next prime is 31621207129. The reversal of 31621207073 is 37070212613.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 8950484449 + 22670722624 = 94607^2 + 150568^2 .

It is a cyclic number.

It is not a de Polignac number, because 31621207073 - 2² = 31621207069 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31621207873) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 385624436 + ... + 385624517.

It is an arithmetic number, because the mean of its divisors is an integer number (8098114017).

Almost surely, 2^31621207073 is an apocalyptic number.

It is an amenable number.

31621207073 is a deficient number, since it is larger than the sum of its proper divisors (771248995).

31621207073 is an equidigital number, since it uses as much as digits as its factorization.

31621207073 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 771248994.

The product of its (nonzero) digits is 10584, while the sum is 32.

Adding to 31621207073 its reverse (37070212613), we get a palindrome (68691419686).

The spelling of 31621207073 in words is "thirty-one billion, six hundred twenty-one million, two hundred seven thousand, seventy-three".