1021012111501 has 2 divisors, whose sum is σ = 1021012111502. Its totient is φ = 1021012111500.

The previous prime is 1021012111499. The next prime is 1021012111543. The reversal of 1021012111501 is 1051112101201.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 788037921225 + 232974190276 = 887715^2 + 482674^2 .

It is a cyclic number.

It is not a de Polignac number, because 1021012111501 - 2¹ = 1021012111499 is a prime.

It is a super-4 number, since 4×1021012111501⁴ (a number of 49 digits) contains 4444 as substring.

Together with 1021012111499, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1021012111901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 510506055750 + 510506055751.

It is an arithmetic number, because the mean of its divisors is an integer number (510506055751).

Almost surely, 2^{1021012111501} is an apocalyptic number.

It is an amenable number.

1021012111501 is a deficient number, since it is larger than the sum of its proper divisors (1).

1021012111501 is an equidigital number, since it uses as much as digits as its factorization.

1021012111501 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 20, while the sum is 16.

Adding to 1021012111501 its reverse (1051112101201), we get a palindrome (2072124212702).

The spelling of 1021012111501 in words is "one trillion, twenty-one billion, twelve million, one hundred eleven thousand, five hundred one".