31887490903801 has 9 divisors (see below), whose sum is σ = 34529137688781. Its totient is φ = 29434539225312.

The previous prime is 31887490903771. The next prime is 31887490903883. The reversal of 31887490903801 is 10830909478813.

The square root of 31887490903801 is 5646901.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 13008292103401 + 18879198800400 = 3606701^2 + 4345020^2 .

It is not a de Polignac number, because 31887490903801 - 2²³ = 31887482515193 is a prime.

It is a super-2 number, since 2×31887490903801² (a number of 28 digits) contains 22 as substring.

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 31887490903801.

It is not an unprimeable number, because it can be changed into a prime (31887490903201) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 73192525 + ... + 73626901.

It is an arithmetic number, because the mean of its divisors is an integer number (3836570854309).

Almost surely, 2^{31887490903801} is an apocalyptic number.

31887490903801 is the 5646901-st square number.

31887490903801 is the 2823451-st centered octagonal number.

It is an amenable number.

31887490903801 is a deficient number, since it is larger than the sum of its proper divisors (2641646784980).

31887490903801 is an frugal number, since it uses more digits than its factorization.

31887490903801 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 868780 (or 434390 counting only the distinct ones).

The product of its (nonzero) digits is 10450944, while the sum is 61.

The spelling of 31887490903801 in words is "thirty-one trillion, eight hundred eighty-seven billion, four hundred ninety million, nine hundred three thousand, eight hundred one".