2961821 has 2 divisors, whose sum is σ = 2961822. Its totient is φ = 2961820.

The previous prime is 2961809. The next prime is 2961823. The reversal of 2961821 is 1281692.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2937796 + 24025 = 1714^2 + 155^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2961821 is a prime.

Together with 2961823, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2961823) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1480910 + 1480911.

It is an arithmetic number, because the mean of its divisors is an integer number (1480911).

2^2961821 is an apocalyptic number.

It is an amenable number.

2961821 is a deficient number, since it is larger than the sum of its proper divisors (1).

2961821 is an equidigital number, since it uses as much as digits as its factorization.

2961821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1728, while the sum is 29.

The square root of 2961821 is about 1720.9941894149. The cubic root of 2961821 is about 143.6105248297.

The spelling of 2961821 in words is "two million, nine hundred sixty-one thousand, eight hundred twenty-one".