263950881531 has 12 divisors (see below), whose sum is σ = 372641718456. Its totient is φ = 165613937280.

The previous prime is 263950881529. The next prime is 263950881553. The reversal of 263950881531 is 135188059362.

It is a happy number.

It is not a de Polignac number, because 263950881531 - 2¹ = 263950881529 is a prime.

It is a super-2 number, since 2×263950881531² (a number of 24 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (51).

It is not an unprimeable number, because it can be changed into a prime (263950881431) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3633021 + ... + 3704961.

It is an arithmetic number, because the mean of its divisors is an integer number (31053476538).

Almost surely, 2^263950881531 is an apocalyptic number.

263950881531 is a deficient number, since it is larger than the sum of its proper divisors (108690836925).

263950881531 is an frugal number, since it uses more digits than its factorization.

263950881531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 143902 (or 71961 counting only the distinct ones).

The product of its (nonzero) digits is 1555200, while the sum is 51.

Multiplying 263950881531 by its sum of digits (51), we get a square (13461494958081 = 3668991²).

263950881531 divided by its sum of digits (51) gives a square (5175507481 = 71941²).

The spelling of 263950881531 in words is "two hundred sixty-three billion, nine hundred fifty million, eight hundred eighty-one thousand, five hundred thirty-one".