1651661672 has 8 divisors (see below), whose sum is σ = 3096865650. Its totient is φ = 825830832.

The previous prime is 1651661653. The next prime is 1651661677. The reversal of 1651661672 is 2761661561.

It can be written as a sum of positive squares in only one way, i.e., 946546756 + 705114916 = 30766^2 + 26554^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is not an unprimeable number, because it can be changed into a prime (1651661677) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 103228847 + ... + 103228862.

Almost surely, 2^1651661672 is an apocalyptic number.

It is an amenable number.

1651661672 is a deficient number, since it is larger than the sum of its proper divisors (1445203978).

1651661672 is a wasteful number, since it uses less digits than its factorization.

1651661672 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 206457715 (or 206457711 counting only the distinct ones).

The product of its digits is 90720, while the sum is 41.

The square root of 1651661672 is about 40640.6406445568. The cubic root of 1651661672 is about 1182.0622923091.

The spelling of 1651661672 in words is "one billion, six hundred fifty-one million, six hundred sixty-one thousand, six hundred seventy-two".