2157645707 has 4 divisors (see below), whose sum is σ = 2465880816. Its totient is φ = 1849410600.

The previous prime is 2157645641. The next prime is 2157645727. The reversal of 2157645707 is 7075467512.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 2157645707 - 2¹⁰ = 2157644683 is a prime.

It is not an unprimeable number, because it can be changed into a prime (2157645727) 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, 154117544 + ... + 154117557.

It is an arithmetic number, because the mean of its divisors is an integer number (616470204).

Almost surely, 2^2157645707 is an apocalyptic number.

2157645707 is a deficient number, since it is larger than the sum of its proper divisors (308235109).

2157645707 is an equidigital number, since it uses as much as digits as its factorization.

2157645707 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 308235108.

The product of its (nonzero) digits is 411600, while the sum is 44.

The square root of 2157645707 is about 46450.4650891678. The cubic root of 2157645707 is about 1292.1909978681.

The spelling of 2157645707 in words is "two billion, one hundred fifty-seven million, six hundred forty-five thousand, seven hundred seven".