102070021 has 6 divisors (see below), whose sum is σ = 106701350. Its totient is φ = 97631688.

The previous prime is 102069991. The next prime is 102070039. The reversal of 102070021 is 120070201.

It can be written as a sum of positive squares in only one way, i.e., 92428996 + 9641025 = 9614^2 + 3105^2 .

It is not a de Polignac number, because 102070021 - 2⁹ = 102069509 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 102069983 and 102070010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (102070051) 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 in 5 ways as a sum of consecutive naturals, for example, 95946 + ... + 97003.

Almost surely, 2^102070021 is an apocalyptic number.

It is an amenable number.

102070021 is a deficient number, since it is larger than the sum of its proper divisors (4631329).

102070021 is an equidigital number, since it uses as much as digits as its factorization.

102070021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 192995 (or 192972 counting only the distinct ones).

The product of its (nonzero) digits is 28, while the sum is 13.

The square root of 102070021 is about 10102.9708996908. The cubic root of 102070021 is about 467.3397637817.

The spelling of 102070021 in words is "one hundred two million, seventy thousand, twenty-one".