1651409 has 2 divisors, whose sum is σ = 1651410. Its totient is φ = 1651408.

The previous prime is 1651387. The next prime is 1651411. The reversal of 1651409 is 9041561.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1345600 + 305809 = 1160^2 + 553^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1651409 is a prime.

Together with 1651411, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (1651609) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 825704 + 825705.

It is an arithmetic number, because the mean of its divisors is an integer number (825705).

2^1651409 is an apocalyptic number.

It is an amenable number.

1651409 is a deficient number, since it is larger than the sum of its proper divisors (1).

1651409 is an equidigital number, since it uses as much as digits as its factorization.

1651409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1080, while the sum is 26.

The square root of 1651409 is about 1285.0715933363. The cubic root of 1651409 is about 118.2002011748.

The spelling of 1651409 in words is "one million, six hundred fifty-one thousand, four hundred nine".