31242731520 has 960 divisors, whose sum is σ = 135287341056. Its totient is φ = 5945425920.

The previous prime is 31242731483. The next prime is 31242731539. The reversal of 31242731520 is 2513724213.

It is a tau number, because it is divible by the number of its divisors (960).

It is a super-2 number, since 2×31242731520² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 246005697 + ... + 246005823.

Almost surely, 2^31242731520 is an apocalyptic number.

31242731520 is a gapful number since it is divisible by the number (30) 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 31242731520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (67643670528).

31242731520 is an abundant number, since it is smaller than the sum of its proper divisors (104044609536).

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

31242731520 is a wasteful number, since it uses less digits than its factorization.

31242731520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 194 (or 168 counting only the distinct ones).

The product of its (nonzero) digits is 10080, while the sum is 30.

The spelling of 31242731520 in words is "thirty-one billion, two hundred forty-two million, seven hundred thirty-one thousand, five hundred twenty".