731131021 has 8 divisors (see below), whose sum is σ = 755545824. Its totient is φ = 707053200.

The previous prime is 731130973. The next prime is 731131031. The reversal of 731131021 is 120131137.

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

It is a cyclic number.

It is not a de Polignac number, because 731131021 - 2¹³ = 731122829 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 731131021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (731131031) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 79831 + ... + 88516.

It is an arithmetic number, because the mean of its divisors is an integer number (94443228).

Almost surely, 2^731131021 is an apocalyptic number.

It is an amenable number.

731131021 is a deficient number, since it is larger than the sum of its proper divisors (24414803).

731131021 is a wasteful number, since it uses less digits than its factorization.

731131021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 168491.

The product of its (nonzero) digits is 126, while the sum is 19.

The square root of 731131021 is about 27039.4345539991. The cubic root of 731131021 is about 900.8761102431.

Adding to 731131021 its reverse (120131137), we get a palindrome (851262158).

The spelling of 731131021 in words is "seven hundred thirty-one million, one hundred thirty-one thousand, twenty-one".