1021400115551 has 2 divisors, whose sum is σ = 1021400115552. Its totient is φ = 1021400115550.

The previous prime is 1021400115521. The next prime is 1021400115601. The reversal of 1021400115551 is 1555110041201.

It is a happy number.

It is a weak prime.

It is an emirp because it is prime and its reverse (1555110041201) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1021400115551 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1021400115551.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1021400115511) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 510700057775 + 510700057776.

It is an arithmetic number, because the mean of its divisors is an integer number (510700057776).

Almost surely, 2^{1021400115551} is an apocalyptic number.

1021400115551 is a deficient number, since it is larger than the sum of its proper divisors (1).

1021400115551 is an equidigital number, since it uses as much as digits as its factorization.

1021400115551 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1000, while the sum is 26.

Adding to 1021400115551 its reverse (1555110041201), we get a palindrome (2576510156752).

The spelling of 1021400115551 in words is "one trillion, twenty-one billion, four hundred million, one hundred fifteen thousand, five hundred fifty-one".