7217640977 has 4 divisors (see below), whose sum is σ = 7281514020. Its totient is φ = 7153767936.

The previous prime is 7217640973. The next prime is 7217641009. The reversal of 7217640977 is 7790467127.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7790467127 = 6781 ⋅1148867.

It can be written as a sum of positive squares in 2 ways, for example, as 1828759696 + 5388881281 = 42764^2 + 73409^2 .

It is a cyclic number.

It is not a de Polignac number, because 7217640977 - 2² = 7217640973 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7217640973) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 31936352 + ... + 31936577.

It is an arithmetic number, because the mean of its divisors is an integer number (1820378505).

Almost surely, 2^7217640977 is an apocalyptic number.

It is an amenable number.

7217640977 is a deficient number, since it is larger than the sum of its proper divisors (63873043).

7217640977 is a wasteful number, since it uses less digits than its factorization.

7217640977 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63873042.

The product of its (nonzero) digits is 1037232, while the sum is 50.

The square root of 7217640977 is about 84956.7006009532. The cubic root of 7217640977 is about 1932.5545362993.

The spelling of 7217640977 in words is "seven billion, two hundred seventeen million, six hundred forty thousand, nine hundred seventy-seven".