16640651 has 2 divisors, whose sum is σ = 16640652. Its totient is φ = 16640650.

The previous prime is 16640647. The next prime is 16640681. The reversal of 16640651 is 15604661.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 16640651 - 2² = 16640647 is a prime.

It is a super-2 number, since 2×16640651² = 553822531407602, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (16640621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8320325 + 8320326.

It is an arithmetic number, because the mean of its divisors is an integer number (8320326).

Almost surely, 2^16640651 is an apocalyptic number.

16640651 is a deficient number, since it is larger than the sum of its proper divisors (1).

16640651 is an equidigital number, since it uses as much as digits as its factorization.

16640651 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4320, while the sum is 29.

The square root of 16640651 is about 4079.2954048463. The cubic root of 16640651 is about 255.3035012462.

The spelling of 16640651 in words is "sixteen million, six hundred forty thousand, six hundred fifty-one".