1645408451 has 2 divisors, whose sum is σ = 1645408452. Its totient is φ = 1645408450.

The previous prime is 1645408447. The next prime is 1645408489. The reversal of 1645408451 is 1548045461.

It is an a-pointer prime, because the next prime (1645408489) can be obtained adding 1645408451 to its sum of digits (38).

It is a weak prime.

It is an emirp because it is prime and its reverse (1548045461) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1645408451 - 2² = 1645408447 is a prime.

It is not a weakly prime, because it can be changed into another prime (1645408411) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 822704225 + 822704226.

It is an arithmetic number, because the mean of its divisors is an integer number (822704226).

Almost surely, 2^1645408451 is an apocalyptic number.

1645408451 is a deficient number, since it is larger than the sum of its proper divisors (1).

1645408451 is an equidigital number, since it uses as much as digits as its factorization.

1645408451 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 76800, while the sum is 38.

The square root of 1645408451 is about 40563.6345881382. The cubic root of 1645408451 is about 1180.5686359686.

The spelling of 1645408451 in words is "one billion, six hundred forty-five million, four hundred eight thousand, four hundred fifty-one".