102649979 has 2 divisors, whose sum is σ = 102649980. Its totient is φ = 102649978.

The previous prime is 102649949. The next prime is 102649997. The reversal of 102649979 is 979946201.

Together with next prime (102649997) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-102649979 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (102649919) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 51324989 + 51324990.

It is an arithmetic number, because the mean of its divisors is an integer number (51324990).

Almost surely, 2^102649979 is an apocalyptic number.

102649979 is a deficient number, since it is larger than the sum of its proper divisors (1).

102649979 is an equidigital number, since it uses as much as digits as its factorization.

102649979 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 244944, while the sum is 47.

The square root of 102649979 is about 10131.6325930227. The cubic root of 102649979 is about 468.2232282404.

The spelling of 102649979 in words is "one hundred two million, six hundred forty-nine thousand, nine hundred seventy-nine".