31398005 has 16 divisors (see below), whose sum is σ = 38997504. Its totient is φ = 24251520.

The previous prime is 31397999. The next prime is 31398007. The reversal of 31398005 is 50089313.

It is not a de Polignac number, because 31398005 - 2¹⁴ = 31381621 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31398007) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 20372 + ... + 21858.

It is an arithmetic number, because the mean of its divisors is an integer number (2437344).

Almost surely, 2^31398005 is an apocalyptic number.

It is an amenable number.

31398005 is a deficient number, since it is larger than the sum of its proper divisors (7599499).

31398005 is a wasteful number, since it uses less digits than its factorization.

31398005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1636.

The product of its (nonzero) digits is 3240, while the sum is 29.

The square root of 31398005 is about 5603.3922761127. The cubic root of 31398005 is about 315.4767451296.

The spelling of 31398005 in words is "thirty-one million, three hundred ninety-eight thousand, five".