1631506401 has 24 divisors (see below), whose sum is σ = 2811668640. Its totient is φ = 932288616.

The previous prime is 1631506391. The next prime is 1631506411. The reversal of 1631506401 is 1046051361.

1631506401 is a `hidden beast` number, since 1 + 6 + 3 + 15 + 0 + 640 + 1 = 666.

It is an interprime number because it is at equal distance from previous prime (1631506391) and next prime (1631506411).

It is not a de Polignac number, because 1631506401 - 2⁵ = 1631506369 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (1631506411) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 615271 + ... + 617916.

It is an arithmetic number, because the mean of its divisors is an integer number (117152860).

Almost surely, 2^1631506401 is an apocalyptic number.

It is an amenable number.

1631506401 is a deficient number, since it is larger than the sum of its proper divisors (1180162239).

1631506401 is a wasteful number, since it uses less digits than its factorization.

1631506401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1233210 (or 1233197 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 27.

The square root of 1631506401 is about 40391.9100934828. The cubic root of 1631506401 is about 1177.2343544524.

Adding to 1631506401 its reverse (1046051361), we get a palindrome (2677557762).

The spelling of 1631506401 in words is "one billion, six hundred thirty-one million, five hundred six thousand, four hundred one".