21153131407 has 2 divisors, whose sum is σ = 21153131408. Its totient is φ = 21153131406.

The previous prime is 21153131401. The next prime is 21153131443. The reversal of 21153131407 is 70413135112.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21153131407 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21153131401) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10576565703 + 10576565704.

It is an arithmetic number, because the mean of its divisors is an integer number (10576565704).

Almost surely, 2^21153131407 is an apocalyptic number.

21153131407 is a deficient number, since it is larger than the sum of its proper divisors (1).

21153131407 is an equidigital number, since it uses as much as digits as its factorization.

21153131407 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2520, while the sum is 28.

Adding to 21153131407 its reverse (70413135112), we get a palindrome (91566266519).

The spelling of 21153131407 in words is "twenty-one billion, one hundred fifty-three million, one hundred thirty-one thousand, four hundred seven".