31661231400 has 480 divisors, whose sum is σ = 119776932000. Its totient is φ = 7720634880.

The previous prime is 31661231389. The next prime is 31661231447. The reversal of 31661231400 is 413216613.

31661231400 is a `hidden beast` number, since 3 + 1 + 6 + 612 + 3 + 1 + 40 + 0 = 666.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 8924427 + ... + 8927973.

It is an arithmetic number, because the mean of its divisors is an integer number (249535275).

Almost surely, 2^31661231400 is an apocalyptic number.

31661231400 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31661231400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (59888466000).

31661231400 is an abundant number, since it is smaller than the sum of its proper divisors (88115700600).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

31661231400 is a wasteful number, since it uses less digits than its factorization.

31661231400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3623 (or 3605 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 27.

The spelling of 31661231400 in words is "thirty-one billion, six hundred sixty-one million, two hundred thirty-one thousand, four hundred".