1421028407661 has 16 divisors (see below), whose sum is σ = 2007501568704. Its totient is φ = 891028415744.

The previous prime is 1421028407651. The next prime is 1421028407723. The reversal of 1421028407661 is 1667048201241.

It is a cyclic number.

It is not a de Polignac number, because 1421028407661 - 2¹⁸ = 1421028145517 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1421028407651) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9255171 + ... + 9407456.

It is an arithmetic number, because the mean of its divisors is an integer number (125468848044).

Almost surely, 2^{1421028407661} is an apocalyptic number.

It is an amenable number.

1421028407661 is a deficient number, since it is larger than the sum of its proper divisors (586473161043).

1421028407661 is a wasteful number, since it uses less digits than its factorization.

1421028407661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18664140.

The product of its (nonzero) digits is 129024, while the sum is 42.

The spelling of 1421028407661 in words is "one trillion, four hundred twenty-one billion, twenty-eight million, four hundred seven thousand, six hundred sixty-one".