31561001472 has 480 divisors, whose sum is σ = 113583444480. Its totient is φ = 7562280960.

The previous prime is 31561001471. The next prime is 31561001473. The reversal of 31561001472 is 27410016513.

It is an interprime number because it is at equal distance from previous prime (31561001471) and next prime (31561001473).

It is not an unprimeable number, because it can be changed into a prime (31561001471) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 19987179 + ... + 19988757.

It is an arithmetic number, because the mean of its divisors is an integer number (236632176).

Almost surely, 2^31561001472 is an apocalyptic number.

31561001472 is a gapful number since it is divisible by the number (32) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31561001472, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (56791722240).

31561001472 is an abundant number, since it is smaller than the sum of its proper divisors (82022443008).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

31561001472 is a wasteful number, since it uses less digits than its factorization.

31561001472 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1644 (or 1615 counting only the distinct ones).

The product of its (nonzero) digits is 5040, while the sum is 30.

Adding to 31561001472 its reverse (27410016513), we get a palindrome (58971017985).

The spelling of 31561001472 in words is "thirty-one billion, five hundred sixty-one million, one thousand, four hundred seventy-two".