1661211522 has 48 divisors (see below), whose sum is σ = 3717342720. Its totient is φ = 535841856.

The previous prime is 1661211521. The next prime is 1661211523. The reversal of 1661211522 is 2251121661.

1661211522 is a `hidden beast` number, since 16 + 6 + 121 + 1 + 522 = 666.

It is an interprime number because it is at equal distance from previous prime (1661211521) and next prime (1661211523).

It is not an unprimeable number, because it can be changed into a prime (1661211521) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 64263 + ... + 86325.

It is an arithmetic number, because the mean of its divisors is an integer number (77444640).

Almost surely, 2^1661211522 is an apocalyptic number.

1661211522 is an abundant number, since it is smaller than the sum of its proper divisors (2056131198).

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

1661211522 is a wasteful number, since it uses less digits than its factorization.

1661211522 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22207 (or 22204 counting only the distinct ones).

The product of its digits is 1440, while the sum is 27.

The square root of 1661211522 is about 40757.9626821557. The cubic root of 1661211522 is about 1184.3361297798.

The spelling of 1661211522 in words is "one billion, six hundred sixty-one million, two hundred eleven thousand, five hundred twenty-two".