31420721773 has 8 divisors (see below), whose sum is σ = 35912699648. Its totient is φ = 26929569744.

The previous prime is 31420721749. The next prime is 31420721791. The reversal of 31420721773 is 37712702413.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 31420721773 - 2²⁹ = 30883850861 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31420721873) 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 in 7 ways as a sum of consecutive naturals, for example, 122661 + ... + 279082.

It is an arithmetic number, because the mean of its divisors is an integer number (4489087456).

Almost surely, 2^31420721773 is an apocalyptic number.

It is an amenable number.

31420721773 is a deficient number, since it is larger than the sum of its proper divisors (4491977875).

31420721773 is a wasteful number, since it uses less digits than its factorization.

31420721773 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 412923.

The product of its (nonzero) digits is 49392, while the sum is 37.

The spelling of 31420721773 in words is "thirty-one billion, four hundred twenty million, seven hundred twenty-one thousand, seven hundred seventy-three".