977892221 has 2 divisors, whose sum is σ = 977892222. Its totient is φ = 977892220.

The previous prime is 977892193. The next prime is 977892229. The reversal of 977892221 is 122298779.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 552955225 + 424936996 = 23515^2 + 20614^2 .

It is a cyclic number.

It is not a de Polignac number, because 977892221 - 2¹⁴ = 977875837 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (977892229) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 488946110 + 488946111.

It is an arithmetic number, because the mean of its divisors is an integer number (488946111).

Almost surely, 2^977892221 is an apocalyptic number.

It is an amenable number.

977892221 is a deficient number, since it is larger than the sum of its proper divisors (1).

977892221 is an equidigital number, since it uses as much as digits as its factorization.

977892221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 254016, while the sum is 47.

The square root of 977892221 is about 31271.2682985516. The cubic root of 977892221 is about 992.5757573611.

The spelling of 977892221 in words is "nine hundred seventy-seven million, eight hundred ninety-two thousand, two hundred twenty-one".