1661521463622 has 40 divisors (see below), whose sum is σ = 3723112935432. Its totient is φ = 553829464800.

The previous prime is 1661521463597. The next prime is 1661521463659. The reversal of 1661521463622 is 2263641251661.

1661521463622 is a `hidden beast` number, since 1 + 6 + 6 + 1 + 5 + 2 + 1 + 4 + 636 + 2 + 2 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 14420722 + ... + 14535482.

Almost surely, 2^{1661521463622} is an apocalyptic number.

1661521463622 is an abundant number, since it is smaller than the sum of its proper divisors (2061591471810).

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

1661521463622 is a wasteful number, since it uses less digits than its factorization.

1661521463622 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 204146 (or 204137 counting only the distinct ones).

The product of its digits is 622080, while the sum is 45.

The spelling of 1661521463622 in words is "one trillion, six hundred sixty-one billion, five hundred twenty-one million, four hundred sixty-three thousand, six hundred twenty-two".