1661263266 has 32 divisors (see below), whose sum is σ = 3587512320. Its totient is φ = 509814144.

The previous prime is 1661263249. The next prime is 1661263277. The reversal of 1661263266 is 6623621661.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2070 + ... + 57678.

It is an arithmetic number, because the mean of its divisors is an integer number (112109760).

Almost surely, 2^1661263266 is an apocalyptic number.

1661263266 is an abundant number, since it is smaller than the sum of its proper divisors (1926249054).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1661263266 is a wasteful number, since it uses less digits than its factorization.

1661263266 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56010.

The product of its digits is 93312, while the sum is 39.

The square root of 1661263266 is about 40758.5974488819. The cubic root of 1661263266 is about 1184.3484263580.

The spelling of 1661263266 in words is "one billion, six hundred sixty-one million, two hundred sixty-three thousand, two hundred sixty-six".