1012620001661 has 16 divisors (see below), whose sum is σ = 1065770879040. Its totient is φ = 960844936320.

The previous prime is 1012620001607. The next prime is 1012620001663. The reversal of 1012620001661 is 1661000262101.

It is a cyclic number.

It is not a de Polignac number, because 1012620001661 - 2¹⁴ = 1012619985277 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1012620001661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1012620001663) 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, 3782930 + ... + 4041756.

It is an arithmetic number, because the mean of its divisors is an integer number (66610679940).

Almost surely, 2^{1012620001661} is an apocalyptic number.

It is an amenable number.

1012620001661 is a deficient number, since it is larger than the sum of its proper divisors (53150877379).

1012620001661 is a wasteful number, since it uses less digits than its factorization.

1012620001661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 261484.

The product of its (nonzero) digits is 864, while the sum is 26.

Adding to 1012620001661 its reverse (1661000262101), we get a palindrome (2673620263762).

The spelling of 1012620001661 in words is "one trillion, twelve billion, six hundred twenty million, one thousand, six hundred sixty-one".