121497840 has 80 divisors (see below), whose sum is σ = 418500000. Its totient is φ = 32398848.

The previous prime is 121497823. The next prime is 121497841. The reversal of 121497840 is 48794121.

121497840 is a `hidden beast` number, since 121 + 497 + 8 + 40 = 666.

It is a tau number, because it is divible by the number of its divisors (80).

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 121497795 and 121497804.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121497841) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 25965 + ... + 30284.

It is an arithmetic number, because the mean of its divisors is an integer number (5231250).

Almost surely, 2^121497840 is an apocalyptic number.

121497840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

121497840 is an abundant number, since it is smaller than the sum of its proper divisors (297002160).

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

121497840 is a wasteful number, since it uses less digits than its factorization.

121497840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56271 (or 56259 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 36.

The square root of 121497840 is about 11022.6058624991. The cubic root of 121497840 is about 495.2861522704.

The spelling of 121497840 in words is "one hundred twenty-one million, four hundred ninety-seven thousand, eight hundred forty".