649978403 has 2 divisors, whose sum is σ = 649978404. Its totient is φ = 649978402.

The previous prime is 649978393. The next prime is 649978409. The reversal of 649978403 is 304879946.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 649978403 - 2⁴ = 649978387 is a prime.

It is not a weakly prime, because it can be changed into another prime (649978409) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 324989201 + 324989202.

It is an arithmetic number, because the mean of its divisors is an integer number (324989202).

Almost surely, 2^649978403 is an apocalyptic number.

649978403 is a deficient number, since it is larger than the sum of its proper divisors (1).

649978403 is an equidigital number, since it uses as much as digits as its factorization.

649978403 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1306368, while the sum is 50.

The square root of 649978403 is about 25494.6740124286. The cubic root of 649978403 is about 866.2295113034.

The spelling of 649978403 in words is "six hundred forty-nine million, nine hundred seventy-eight thousand, four hundred three".