2157205677 has 16 divisors (see below), whose sum is σ = 3140881920. Its totient is φ = 1306094000.

The previous prime is 2157205651. The next prime is 2157205691. The reversal of 2157205677 is 7765027512.

It is a cyclic number.

It is not a de Polignac number, because 2157205677 - 2¹² = 2157201581 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2157205697) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1552 + ... + 65702.

It is an arithmetic number, because the mean of its divisors is an integer number (196305120).

Almost surely, 2^2157205677 is an apocalyptic number.

It is an amenable number.

2157205677 is a deficient number, since it is larger than the sum of its proper divisors (983676243).

2157205677 is a wasteful number, since it uses less digits than its factorization.

2157205677 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65184.

The product of its (nonzero) digits is 205800, while the sum is 42.

The square root of 2157205677 is about 46445.7282965829. The cubic root of 2157205677 is about 1292.1031488048.

The spelling of 2157205677 in words is "two billion, one hundred fifty-seven million, two hundred five thousand, six hundred seventy-seven".