21101401 has 2 divisors, whose sum is σ = 21101402. Its totient is φ = 21101400.

The previous prime is 21101383. The next prime is 21101407. The reversal of 21101401 is 10410112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19536400 + 1565001 = 4420^2 + 1251^2 .

It is a cyclic number.

It is not a de Polignac number, because 21101401 - 2⁷ = 21101273 is a prime.

It is not a weakly prime, because it can be changed into another prime (21101407) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10550700 + 10550701.

It is an arithmetic number, because the mean of its divisors is an integer number (10550701).

Almost surely, 2^21101401 is an apocalyptic number.

It is an amenable number.

21101401 is a deficient number, since it is larger than the sum of its proper divisors (1).

21101401 is an equidigital number, since it uses as much as digits as its factorization.

21101401 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8, while the sum is 10.

The square root of 21101401 is about 4593.6261275816. The cubic root of 21101401 is about 276.3357646117.

Adding to 21101401 its reverse (10410112), we get a palindrome (31511513).

The spelling of 21101401 in words is "twenty-one million, one hundred one thousand, four hundred one".