21357101 has 2 divisors, whose sum is σ = 21357102. Its totient is φ = 21357100.

The previous prime is 21357071. The next prime is 21357107. The reversal of 21357101 is 10175312.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15721225 + 5635876 = 3965^2 + 2374^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21357101 is a prime.

It is a super-2 number, since 2×21357101² = 912251526248402, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21357107) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10678550 + 10678551.

It is an arithmetic number, because the mean of its divisors is an integer number (10678551).

Almost surely, 2^21357101 is an apocalyptic number.

It is an amenable number.

21357101 is a deficient number, since it is larger than the sum of its proper divisors (1).

21357101 is an equidigital number, since it uses as much as digits as its factorization.

21357101 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 210, while the sum is 20.

The square root of 21357101 is about 4621.3743626761. The cubic root of 21357101 is about 277.4474688866.

The spelling of 21357101 in words is "twenty-one million, three hundred fifty-seven thousand, one hundred one".