1000155100661 has 4 divisors (see below), whose sum is σ = 1002159420000. Its totient is φ = 998150781324.

The previous prime is 1000155100657. The next prime is 1000155100687. The reversal of 1000155100661 is 1660015510001.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1000155100661 - 2² = 1000155100657 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1000155100661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1000155100601) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1002158921 + ... + 1002159918.

It is an arithmetic number, because the mean of its divisors is an integer number (250539855000).

Almost surely, 2^{1000155100661} is an apocalyptic number.

It is an amenable number.

1000155100661 is a deficient number, since it is larger than the sum of its proper divisors (2004319339).

1000155100661 is an equidigital number, since it uses as much as digits as its factorization.

1000155100661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2004319338.

The product of its (nonzero) digits is 900, while the sum is 26.

The spelling of 1000155100661 in words is "one trillion, one hundred fifty-five million, one hundred thousand, six hundred sixty-one".