261977963 has 8 divisors (see below), whose sum is σ = 285530448. Its totient is φ = 238911264.

The previous prime is 261977929. The next prime is 261977971. The reversal of 261977963 is 369779162.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 261977963 - 2⁶ = 261977899 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (261977663) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 120320 + ... + 122477.

It is an arithmetic number, because the mean of its divisors is an integer number (35691306).

Almost surely, 2^261977963 is an apocalyptic number.

261977963 is a deficient number, since it is larger than the sum of its proper divisors (23552485).

261977963 is a wasteful number, since it uses less digits than its factorization.

261977963 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 242893.

The product of its digits is 857304, while the sum is 50.

The square root of 261977963 is about 16185.7333167206. The cubic root of 261977963 is about 639.8648502057.

The spelling of 261977963 in words is "two hundred sixty-one million, nine hundred seventy-seven thousand, nine hundred sixty-three".