7645621972 has 6 divisors (see below), whose sum is σ = 13379838458. Its totient is φ = 3822810984.

The previous prime is 7645621969. The next prime is 7645621993. The reversal of 7645621972 is 2791265467.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 7545701956 + 99920016 = 86866^2 + 9996^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 955702743 + ... + 955702750.

Almost surely, 2^7645621972 is an apocalyptic number.

It is an amenable number.

7645621972 is a deficient number, since it is larger than the sum of its proper divisors (5734216486).

7645621972 is a wasteful number, since it uses less digits than its factorization.

7645621972 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1911405497 (or 1911405495 counting only the distinct ones).

The product of its digits is 1270080, while the sum is 49.

The square root of 7645621972 is about 87439.2473206397. The cubic root of 7645621972 is about 1970.0213841547.

The spelling of 7645621972 in words is "seven billion, six hundred forty-five million, six hundred twenty-one thousand, nine hundred seventy-two".