261441431403554 has 4 divisors (see below), whose sum is σ = 392162147105334. Its totient is φ = 130720715701776.

The previous prime is 261441431403547. The next prime is 261441431403569. The reversal of 261441431403554 is 455304134144162.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 143896218705625 + 117545212697929 = 11995675^2 + 10841827^2 .

It is a junction number, because it is equal to n+sod(n) for n = 261441431403499 and 261441431403508.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 65360357850887 + ... + 65360357850890.

Almost surely, 2^{261441431403554} is an apocalyptic number.

261441431403554 is a deficient number, since it is larger than the sum of its proper divisors (130720715701780).

261441431403554 is a wasteful number, since it uses less digits than its factorization.

261441431403554 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 130720715701779.

The product of its (nonzero) digits is 2764800, while the sum is 47.

The spelling of 261441431403554 in words is "two hundred sixty-one trillion, four hundred forty-one billion, four hundred thirty-one million, four hundred three thousand, five hundred fifty-four".