1661400072231 has 8 divisors (see below), whose sum is σ = 2215413158400. Its totient is φ = 1107493517112.

The previous prime is 1661400072209. The next prime is 1661400072251. The reversal of 1661400072231 is 1322700041661.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1661400072231 - 2⁹ = 1661400071719 is a prime.

It is a super-2 number, since 2×1661400072231² (a number of 25 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1661400072192 and 1661400072201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1661400072251) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 26596365 + ... + 26658758.

It is an arithmetic number, because the mean of its divisors is an integer number (276926644800).

Almost surely, 2^{1661400072231} is an apocalyptic number.

1661400072231 is a deficient number, since it is larger than the sum of its proper divisors (554013086169).

1661400072231 is a wasteful number, since it uses less digits than its factorization.

1661400072231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53265525.

The product of its (nonzero) digits is 12096, while the sum is 33.

The spelling of 1661400072231 in words is "one trillion, six hundred sixty-one billion, four hundred million, seventy-two thousand, two hundred thirty-one".