102123521 has 2 divisors, whose sum is σ = 102123522. Its totient is φ = 102123520.

The previous prime is 102123493. The next prime is 102123523. The reversal of 102123521 is 125321201.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 66601921 + 35521600 = 8161^2 + 5960^2 .

It is a cyclic number.

It is not a de Polignac number, because 102123521 - 2¹⁸ = 101861377 is a prime.

Together with 102123523, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 102123521.

It is not a weakly prime, because it can be changed into another prime (102123523) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 51061760 + 51061761.

It is an arithmetic number, because the mean of its divisors is an integer number (51061761).

Almost surely, 2^102123521 is an apocalyptic number.

It is an amenable number.

102123521 is a deficient number, since it is larger than the sum of its proper divisors (1).

102123521 is an equidigital number, since it uses as much as digits as its factorization.

102123521 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 120, while the sum is 17.

The square root of 102123521 is about 10105.6182888530. The cubic root of 102123521 is about 467.4214015633.

Adding to 102123521 its reverse (125321201), we get a palindrome (227444722).

It can be divided in two parts, 1021 and 23521, that added together give a palindrome (24542).

The spelling of 102123521 in words is "one hundred two million, one hundred twenty-three thousand, five hundred twenty-one".