21421400153 has 2 divisors, whose sum is σ = 21421400154. Its totient is φ = 21421400152.

The previous prime is 21421400087. The next prime is 21421400201. The reversal of 21421400153 is 35100412412.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21021520144 + 399880009 = 144988^2 + 19997^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21421400153 is a prime.

It is not a weakly prime, because it can be changed into another prime (21421403153) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10710700076 + 10710700077.

It is an arithmetic number, because the mean of its divisors is an integer number (10710700077).

Almost surely, 2^21421400153 is an apocalyptic number.

It is an amenable number.

21421400153 is a deficient number, since it is larger than the sum of its proper divisors (1).

21421400153 is an equidigital number, since it uses as much as digits as its factorization.

21421400153 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 960, while the sum is 23.

Adding to 21421400153 its reverse (35100412412), we get a palindrome (56521812565).

The spelling of 21421400153 in words is "twenty-one billion, four hundred twenty-one million, four hundred thousand, one hundred fifty-three".