1956477391 has 4 divisors (see below), whose sum is σ = 2134338984. Its totient is φ = 1778615800.

The previous prime is 1956477377. The next prime is 1956477433. The reversal of 1956477391 is 1937746591.

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 1956477391 - 2¹⁷ = 1956346319 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1956477791) 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, 88930780 + ... + 88930801.

It is an arithmetic number, because the mean of its divisors is an integer number (533584746).

Almost surely, 2^1956477391 is an apocalyptic number.

1956477391 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1956477391 is a deficient number, since it is larger than the sum of its proper divisors (177861593).

1956477391 is a wasteful number, since it uses less digits than its factorization.

1956477391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 177861592.

The product of its digits is 1428840, while the sum is 52.

The square root of 1956477391 is about 44232.0855375371. The cubic root of 1956477391 is about 1250.7147679542.

The spelling of 1956477391 in words is "one billion, nine hundred fifty-six million, four hundred seventy-seven thousand, three hundred ninety-one".