20401011391 has 2 divisors, whose sum is σ = 20401011392. Its totient is φ = 20401011390.

The previous prime is 20401011373. The next prime is 20401011427. The reversal of 20401011391 is 19311010402.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20401011391 - 2¹⁷ = 20400880319 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20401011361) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10200505695 + 10200505696.

It is an arithmetic number, because the mean of its divisors is an integer number (10200505696).

Almost surely, 2^20401011391 is an apocalyptic number.

20401011391 is a deficient number, since it is larger than the sum of its proper divisors (1).

20401011391 is an equidigital number, since it uses as much as digits as its factorization.

20401011391 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 216, while the sum is 22.

Adding to 20401011391 its reverse (19311010402), we get a palindrome (39712021793).

The spelling of 20401011391 in words is "twenty billion, four hundred one million, eleven thousand, three hundred ninety-one".