31220440010381 has 2 divisors, whose sum is σ = 31220440010382. Its totient is φ = 31220440010380.

The previous prime is 31220440010339. The next prime is 31220440010407. The reversal of 31220440010381 is 18301004402213.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 30398351440900 + 822088569481 = 5513470^2 + 906691^2 .

It is a cyclic number.

It is not a de Polignac number, because 31220440010381 - 2²² = 31220435816077 is a prime.

It is a super-2 number, since 2×31220440010381² (a number of 28 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31220440013381) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15610220005190 + 15610220005191.

It is an arithmetic number, because the mean of its divisors is an integer number (15610220005191).

Almost surely, 2^{31220440010381} is an apocalyptic number.

It is an amenable number.

31220440010381 is a deficient number, since it is larger than the sum of its proper divisors (1).

31220440010381 is an equidigital number, since it uses as much as digits as its factorization.

31220440010381 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4608, while the sum is 29.

Adding to 31220440010381 its reverse (18301004402213), we get a palindrome (49521444412594).

The spelling of 31220440010381 in words is "thirty-one trillion, two hundred twenty billion, four hundred forty million, ten thousand, three hundred eighty-one".