1264661113561 has 8 divisors (see below), whose sum is σ = 1319705915904. Its totient is φ = 1209621272640.

The previous prime is 1264661113543. The next prime is 1264661113571. The reversal of 1264661113561 is 1653111664621.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 1264661113561 - 2³³ = 1256071178969 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1264661113511) 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, 714720 + ... + 1743601.

It is an arithmetic number, because the mean of its divisors is an integer number (164963239488).

Almost surely, 2^{1264661113561} is an apocalyptic number.

It is an amenable number.

1264661113561 is a deficient number, since it is larger than the sum of its proper divisors (55044802343).

1264661113561 is a wasteful number, since it uses less digits than its factorization.

1264661113561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2480711.

The product of its digits is 155520, while the sum is 43.

The spelling of 1264661113561 in words is "one trillion, two hundred sixty-four billion, six hundred sixty-one million, one hundred thirteen thousand, five hundred sixty-one".