15649649 has 2 divisors, whose sum is σ = 15649650. Its totient is φ = 15649648.

The previous prime is 15649633. The next prime is 15649657. The reversal of 15649649 is 94694651.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15547249 + 102400 = 3943^2 + 320^2 .

It is a cyclic number.

It is not a de Polignac number, because 15649649 - 2⁴ = 15649633 is a prime.

It is a Chen prime.

It is a nialpdrome in base 16.

It is not a weakly prime, because it can be changed into another prime (15649609) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7824824 + 7824825.

It is an arithmetic number, because the mean of its divisors is an integer number (7824825).

Almost surely, 2^15649649 is an apocalyptic number.

It is an amenable number.

15649649 is a deficient number, since it is larger than the sum of its proper divisors (1).

15649649 is an equidigital number, since it uses as much as digits as its factorization.

15649649 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 233280, while the sum is 44.

The square root of 15649649 is about 3955.9637258195. The cubic root of 15649649 is about 250.1313922655.

The spelling of 15649649 in words is "fifteen million, six hundred forty-nine thousand, six hundred forty-nine".