2445551661 has 32 divisors (see below), whose sum is σ = 3770385408. Its totient is φ = 1381086720.

The previous prime is 2445551651. The next prime is 2445551663. The reversal of 2445551661 is 1661555442.

It is not a de Polignac number, because 2445551661 - 2⁵ = 2445551629 is a prime.

It is a Smith number, since the sum of its digits (39) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2445551663) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1174141 + ... + 1176221.

It is an arithmetic number, because the mean of its divisors is an integer number (117824544).

Almost surely, 2^2445551661 is an apocalyptic number.

2445551661 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

2445551661 is a deficient number, since it is larger than the sum of its proper divisors (1324833747).

2445551661 is a wasteful number, since it uses less digits than its factorization.

2445551661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2721.

The product of its digits is 144000, while the sum is 39.

The square root of 2445551661 is about 49452.5192583755. The cubic root of 2445551661 is about 1347.2833638033.

The spelling of 2445551661 in words is "two billion, four hundred forty-five million, five hundred fifty-one thousand, six hundred sixty-one".